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Exothermic - Chem Definition

Video vocabulary

from

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US / frəm /

UK / frʌm, frɑm,frəm /

A1
  • preposition
  • Starting at a particular place, time or level

form

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US / fɔ:m /

UK / fɔrm /

A1
  • noun
  • Sports team or person's current winning record
  • Document you complete when making an application
  • Visible shape or style; type; kind
  • verb
  • To organize something such as a club or group
  • To develop; to come into a shape or substance
  • To make something into a particular shape

hot

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US / hɒt /

UK / hɑ:t /

A1
  • adjecitve
  • Angry or excited
  • Being very good at something
  • Having a high temperature
  • Popular and causing a great deal of excitement
  • Attractive in a sexually exciting way
  • (Of food) very spicy
  • Stolen; dangerous to buy or trade in

out

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US / aʊt /

UK / aʊt /

A1
  • adverb
  • No longer stylish (e.g. fashion)
  • Away from home, business, or the usual place
  • In a direction/movement away from inside or center
  • noun
  • Act when a batter cannot continue playing
  • verb
  • To tell people a secret

over

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US / 'əʊvə(r) /

UK / ˈovɚ /

A1
  • adverb
  • Finished; no longer happening
  • Towards the ground/away from a standing position
  • noun
  • A set of six consecutive balls bowled in cricket
  • other
  • Finished
  • preposition
  • Showing the relation when a thing is above another
  • On or covering something
  • Above or across something
  • More than you need
  • From one side to the other
  • In the direction of; toward

temperature

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US / ˈtemprətʃə(r) /

UK / ˈtɛmpərəˌtʃʊr,-tʃɚ,ˈtɛmprə- /

A2
  • noun
  • When you your body heat is above normal
  • How hot or cold something is, e.g. the weather

react

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US / rɪ'ækt /

UK / riˈækt /

A2
  • verb
  • To change when mixing with other chemicals
  • To behave or make a change in a particular way

any

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US / 'enɪ /

UK / ˈɛni /

A1
  • adjecitve
  • One, or some, no matter which
  • pronoun
  • One (thing) of many; some

come

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US / kʌm /

UK / kʌm /

A1
  • verb
  • To arrive at a place
  • (Of mail) to be delivered
  • To move toward someone; go with someone
  • To reach a certain point or state

think

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US / θɪŋk /

UK / θɪŋk /

A1
  • verb
  • To have an idea about something without certainty
  • To have an idea, opinion or belief about something

and

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US / ənd /

UK / ənd, ən,ænd /

A1
  • conjunction
  • Used to refer to two or more things
  • Plus; in addition; on top of that
  • Used to introduce an action that follows another

back

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US / bæk /

UK / bæk /

A1
  • adjecitve
  • Farthest from the front e.g. in a classroom
  • adverb
  • Have returned to a place you were before
  • noun
  • The part of a chair that the upper body leans upon
  • Location at the rear of something
  • The reverse of side something
  • Area on the rear of your body
  • verb
  • To bet money on something
  • To go backwards in a car
  • To support and encourage someone or some cause

hopefully

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US / ˈhəʊpfəli /

UK / ˈhopfəli /

A2
  • adverb
  • In a manner wishing something to happen

lot

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US / lɒt /

UK / lɑt /

A1
  • noun
  • What happens to a person in life from chance; fate
  • A group of people seen together
  • Item for sale at an auction
  • Small area of land used for a purpose e.g. parking

large

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US / lɑ:dʒ /

UK / lɑ:rdʒ /

A1
  • adjecitve
  • Big; of great size; broad, tall, wide, or fat

distil

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US / dɪˈstɪl /

UK / dɪˈstɪl /

B2
  • verb
  • To collect the pure form by heating liquid

keep

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US / ki:p /

UK / kip /

A1
  • noun
  • Large, strong tower in the middle of a castle
  • Money spent on you so you can live in a place
  • verb
  • To continue doing something; not to stop
  • To stop balls going in a goal in sports
  • To not give back or return something
  • (Of food) to not spoil or not rot
  • To take possession of something to own, e.g. a pet
  • To have and continue to hold something
  • To do something that you have promised or agreed
  • To stay in a certain place or condition
  • To maintain the rules

rather

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US / 'rɑ:ðə(r) /

UK / ˈræðɚ, ˈrɑðɚ /

A1
  • adverb
  • Somewhat; fairly; not that much

something

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US / ˈsʌmθɪŋ /

UK / ˈsʌmθɪŋ /

A1
  • adverb
  • In some degree or measure
  • noun
  • a person or thing of some value or consequence
  • pronoun
  • Thing that is not yet known or named
  • Approximately

approximately

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US / əˈprɒksɪmətli /

UK / əˈprɑksəmɪtlɪ /

A2
  • adverb
  • Around; nearly; almost; about (a number)

call

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US / kɔ:l /

UK / kɔl /

A1
  • noun
  • A order or request for action
  • The sound an animal makes, often when in danger
  • A correct prediction, e.g. a decision in a game
  • A short visit to a place or person
  • A decision by a referee or umpire in a game
  • verb
  • To make a request or order for action
  • (Animal) to make sounds to warn of danger
  • To announce the date of an election
  • To make a judgment about something
  • To give someone or something a name
  • To guess in advance the result or outcome
  • To visit a place or person for a short time
  • To phone someone
  • To speak, announce or shout in a loud voice

where

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US / hwɛə /

UK / hwɛr, wɛr /

A1
  • conjunction
  • At or in the place which
  • In whatever place
  • pronoun
  • Word you use to ask the location of something

put

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US / pʊt /

UK / pʊt /

A1
  • phrasal verb
  • to make a light stop shining by pressing or moving a switch
  • verb
  • To move or place a thing in a particular position
  • To rate something in importance or value
  • To write or say something in a certain manner

release

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US / rɪ'li:s /

UK / rɪ'li:s /

A2
  • noun
  • Act of freeing someone from a duty or burden
  • Introduction of a new product, film, book, etc.
  • Relief from sadness, suffering or trouble
  • Act of freeing from a jail, cage, prison, etc.
  • verb
  • To free someone from a responsibility or burden
  • To allow a film, music etc. to be sold/distributed
  • To allow to leave a jail, cage, etc.; let out
  • To let go of something you are holding

pig

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US / pɪg /

UK / pɪɡ /

B1
  • noun
  • Animal that bacon, pork and ham come from
  • Greedy person
  • Someone disgusting, e.g. in being dirty or rude

solid

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US / 'sɒlɪd /

UK / ˈsɑlɪd /

A2
  • adjecitve
  • Being able to be trusted; reliable
  • Substance that is hard or of fixed shape
  • Being well made and expected to last long
  • Having no space or emptiness inside
  • Being made entirely of one material or substance
  • noun
  • Something firm or hard; not gas or liquid

worth

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US / wɜ:θ /

UK / wɚθ /

A2
  • other
  • the financial, practical or moral value of somebody/something
  • having a particular value, especially in money

set

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US / set /

UK / sɛt /

A1
  • adjecitve
  • Prepared for something; ready
  • noun
  • Complete group of something
  • Place where a television show or movie is filmed
  • Group of games in a tennis match
  • Device that receives radio or television signals
  • verb
  • To make a clock state or ring at a particular time
  • To decide upon or choose something
  • To make something ready for use (e.g. table)
  • To decide on a price for something
  • To become hard (of glue, concrete etc.)
  • To be located in a specific place or time
  • To put (e.g. a vase) down carefully in a place
  • To put someone in a certain condition or state
  • (Of the sun) to go lower than the horizon

well

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US / wel /

UK / wɛl /

A1
  • adjecitve
  • Being in a fortunate, good condition or state
  • Healthy and in good condition
  • adverb
  • In an acceptable, proper, or successful manner
  • In a complete, total, or full manner
  • A great and considerable degree
  • In a successful way, in a good or satisfactory way
  • exclamation
  • Used to begin or continue a particular statement
  • Used to show you want to start saying something
  • Used to express that you are waiting for a reply
  • You say this to change the topic of a conversation
  • Used to indicate you are making a final remark
  • noun
  • Long deep hole in the ground to get water
  • verb
  • To cause your eyes to fill with tears

start

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US / stɑ:t /

UK / stɑrt /

A1
  • noun
  • First time or place that a thing exists; beginning
  • First opportunity to achieve something, e.g. a job
  • Sudden action or movement because you are scared
  • other
  • Beginning of something in place or time
  • verb
  • To do, be or happen for the first time; begin
  • To turn something on

within

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US / wɪˈðɪn /

UK / wɪðˈɪn, wɪθ- /

A1
  • adverb
  • Inside the limits of an area, time or range
  • preposition
  • From the inside of something

exothermic

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US / ˌeksəʊˈθɜ:mɪk /

UK / ˌeksoʊˈθɜ:rmɪk /

A1
  • adjecitve
  • Occurring or formed with the liberation of heat

definitely

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US / ˈdefɪnətli /

UK / ˈdefɪnətli /

A2
  • adverb
  • Without question; beyond doubt

sound

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US / saʊnd /

UK / saʊnd /

A1
  • adjecitve
  • Sensible, dependable and reliable
  • Unbroken or undisturbed, as of sleep
  • Firm or solid in structure
  • Sane; not mentally ill
  • Clearly reasoned; involving sense, good judgment
  • noun
  • Unique quality that characterizes a style of music
  • Waves traveling in air or water that can be heard
  • verb
  • To seem or appear to be, from what was said
  • To say in a clear deliberate manner
  • To make a noise, e.g. to ring a bell

warm

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US / wɔ:m /

UK / wɔrm /

A1
  • adjecitve
  • Friendly, sincere and kind to others
  • Being friendly or sincere
  • Slightly hot; not very hot
  • verb
  • To become more friendly or to like something
  • To make something hotter

water

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US / 'wɔ:tə(r) /

UK / ˈwɔtɚ, ˈwɑtɚ /

A1
  • noun
  • Clear liquid that forms the seas, rivers and rain
  • Large area such as an ocean or sea
  • verb
  • (Of the eyes) to produce tears
  • (Mouth) to become wet at the thought of nice food
  • To pour liquids onto a plant to keep it alive

cold

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US / kəʊld /

UK / kold /

A1
  • adjecitve
  • Having a very low temperature
  • Being unfriendly or lacking emotion
  • noun
  • Illness of sneezing, coughing, and a sore throat

much

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US / mʌtʃ /

UK / mʌtʃ /

A1
  • adjecitve
  • Very; to a high level or degree
  • adverb
  • A lot; large amount; a high degree of
  • Nearly; basically
  • On many occasions; often
  • noun
  • A large amount; a great quantity

oil

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US / ɔɪl /

UK / ɔɪl /

A2
  • noun
  • A liquid used for frying foods
  • Thick, black liquid in the ground used as fuel
  • verb
  • To add a liquid for frying foods
  • To put liquid in a machine so it will run smoothly

strong

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US / strɒŋ /

UK / strɔŋ /

A1
  • adjecitve
  • (Of tea or beer) dark or thick
  • Having big muscles; physically powerful

just

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US / dʒʌst /

UK / dʒʌst /

A1
  • adjecitve
  • Proper or appropriate; as is deserved
  • Doing or being what is right or fair
  • Legally correct; having enough evidence
  • adverb
  • Almost; nearly
  • Exactly at the time of
  • Exactly (the same as, like)

fume

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US / fju:m /

UK / fjum /

B1
  • other
  • Unpleasant smoke or gas, e.g. from cars
  • verb
  • To feel angry; show that one is angry
  • To produce unpleasant smoke or gas

generate

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US / ˈdʒenəreɪt /

UK / ˈdʒɛnəˌret /

A2
  • verb
  • To create or be produced or bring into existence
  • To create electricity, heat, energy and power

shoot

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US / ʃu:t /

UK / ʃut /

A2
  • noun
  • Emerging new part of a plant
  • verb
  • To kick or throw a ball at a goal
  • To fire a gun; injure or kill someone with a gun
  • To (cause to) fly away forcefully
  • To use a camera to record a film/take a photograph

wrap

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US / ræp /

UK / ræp /

B1
  • noun
  • Piece of clothing worn loosely on the shoulders
  • Thin bread filled with food and rolled
  • verb
  • To be or move around something
  • To cover something with paper or a cloth e.g. gift

occur

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US / əˈkɜ:(r) /

UK / əˈkɚ /

A2
  • verb
  • To come to pass or to happen

pop

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US / pɒp /

UK / pɑp /

B2
  • adjecitve
  • Type of music or art popular with many people
  • noun
  • Sweet soda drink
  • verb
  • To cause something to open or burst suddenly
  • To go to or in a place for a brief period of time

though

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US / ðəu /

UK / ðo /

A1
  • adverb
  • Although, despite the fact that

should

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US / ʃʊd /

UK / ʃʊd /

A1
  • other
  • Used to indicate what is proper or reasonable

sweat

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US / swet /

UK / swɛt /

A2
  • noun
  • An amount of hard work
  • (Of work, job) hard; needing effort
  • Liquid from your skin when you are hot or nervous
  • verb
  • To do an amount of hard work
  • To be worried or anxious about something
  • To produce drops of water from your skin when hot

white

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US / waɪt /

UK / hwaɪt, waɪt /

A1
  • adjecitve
  • Belonging to a race of people with light skin
  • Of the color of fresh snow and milk
  • noun
  • Person's name
  • Lightest color; The color of fresh snow.

either

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US / ˈaɪðə(r) /

UK / ˈiðɚ, ˈaɪðɚ /

A1
  • adjecitve
  • One of two (used when there is a choice of two)
  • adverb
  • (After negative statements) likewise, in addition
  • conjunction
  • Used as the first of two connected things
  • determiner
  • Used as the first of two connected things
  • pronoun
  • The one or the other

here

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US / hɪə(r) /

UK / hɪr /

A1
  • adverb
  • In this place; at this location, position or time

new

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US / nju: /

UK / nu, nju /

A1
  • adjecitve
  • Not old, recently born, built or made
  • Being or doing something for the first time
  • Not felt, seen or known previously
  • Having been recently bought or obtained

small

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US / smɔ:l /

UK / smɔl /

A1
  • adjecitve
  • Little in size; not big
  • (Of letters) not written in capital letters
  • Being insignificant or minor
  • (Of a business) with few people or things; local
  • (Of voice) being soft and quiet
  • (Of a child) being young

area

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US / 'eərɪə /

UK / ˈɛriə /

A1
  • noun
  • Amount of measured space
  • A specific section or space; part of a region
  • A subject or field of study

feel

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US / fi:l /

UK / fil /

A1
  • verb
  • To be aware of or experience an emotion, sensation
  • To sense through direct contact; touch

too

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US / tu: /

UK / tu /

A1
  • adverb
  • In addition, also; with emphasis
  • Say that something is more than you want

dramatically

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US / drə'mætɪklɪ /

UK / drəˈmætɪkl:ɪ /

B1
  • adverb
  • In a sudden or extreme manner

day

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US / deɪ /

UK / de /

A1
  • noun
  • A period of 24 hours beginning at midnight
  • The period of time when it is light outside
  • Person's name

pleasantly

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US / 'plezntlɪ /

UK / ˈplɛzn:tlɪ /

B1
  • adverb
  • In a cheerful manner

actually

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US / ˈæktʃuəli /

UK / ˈæktʃuəli /

A1
  • adverb
  • Used to add new (often different) information

bond

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US / bɒnd /

UK / bɑnd /

A2
  • noun
  • Rope, chain or other thing used to tie someone up
  • Closeness that is shared between people or groups
  • Loan that a government must buy back by a set date
  • Written agreement to pay back borrowed money
  • Joint or connection, often using glue
  • verb
  • To develop a close relationship with
  • To become joined or connected, e.g. using glue

immediately

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US / ɪˈmi:diətli /

UK / ɪˈmidiɪtli /

A1
  • adverb
  • Without any delay; straight away

container

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US / kənˈteɪnə(r) /

UK / kənˈtenɚ /

A2
  • noun
  • An object that can be used to hold things

many

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US / 'menɪ /

UK / ˈmɛni /

A1
  • determiner
  • Used to refer a large number of things

quicklime

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US / ˈkwɪklaɪm /

UK / ˈkwɪkˌlaɪm /

A1
  • noun
  • White crystalline oxide used in the production of calcium hydroxide

will

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US / wɪl /

UK / wɪl /

A1
  • noun
  • Desire or choice of someone
  • Document saying who gets your money when you die
  • Strong desire to do something; determination
  • Desire to do something; strong wish to do
  • other
  • Used with verbs to express the future
  • verb
  • To leave property to someone after your death
  • To use mental effort to make something happen
  • Am (is, are) likely to do
  • To influence someone to do something
  • To make something happen by strongly wanting it

burn

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US / bɜ:n /

UK / bɚn /

A1
  • noun
  • Damage from fire or heat
  • verb
  • To destroy with fire
  • To feel pain and heat
  • To use as fuel for a fire to make light or heat
  • To overcook food with too much heat it goes black

eat

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US / i:t /

UK / it /

A1
  • verb
  • To put food in your mouth

inside

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US / ˌɪn'saɪd /

UK / ɪnˈsaɪd, ˈɪnˌsaɪd /

A2
  • adjecitve
  • Being in something
  • Being in a building
  • adverb
  • Into a house; indoors
  • noun
  • Inner part or surface of something

heat

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US / hi:t /

UK / hit /

A2
  • noun
  • State of anger, excitement, or arguing
  • Particular temperature at which to cook something
  • High temperature
  • One of series of races to find the finalists
  • Hot temperature, conditions, or weather
  • verb
  • To make hot or hotter

safe

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US / seɪf /

UK / sef /

A2
  • noun
  • Metal box with a lock to keep valuable things in
  • adjecitve
  • Highly likely
  • Being out of danger

while

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US / waɪl /

UK / hwaɪl, waɪl /

A1
  • conjunction
  • In spite of the fact that; although
  • During the time that; at the same time
  • noun
  • Short amount of time

about

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US / ə'baʊt /

UK / əˈbaʊt /

A1
  • adverb
  • To be ready to; going to
  • Nearly; approximately; roughly
  • Near; next to; close to
  • In every direction; in the area of
  • preposition
  • Concerning or of (a topic)

even

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US / 'i:vn /

UK / ˈivən /

A1
  • adjecitve
  • Being equal in influence, power, possibility etc.
  • Being divided equally or fairly
  • (Of teams/contest) with similar chances of success
  • Smooth, level, or regular
  • Can be divided by 2; ending in 2, 4, 6, 8, or 0
  • At a regular, equally steady manner
  • Remaining steady and unchanging
  • adverb
  • (When this is surprising) as well; too
  • (Used to compare two things/stress the difference)
  • verb
  • To make something level; to flatten
  • To make something equal

like

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US / laɪk /

UK / laɪk /

A1
  • adjecitve
  • Being equal in status or kind to something else
  • Similar; the same
  • adverb
  • For example
  • preposition
  • Used as a filler; used to ad emphasis
  • In a way similar to the way something is done
  • Such as; for example
  • verb
  • To want to
  • To find something pleasing; to prefer something

reaction

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US / rɪ'ækʃn /

UK / riˈækʃən /

A2
  • noun
  • Bodily response to a drug or something eaten
  • Feeling or action in response to something

people

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US / 'pi:pl /

UK / ˈpipəl /

A1
  • noun
  • Persons sharing culture, country, background, etc.
  • Men, Women, Children

that

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US / ðæt /

UK / ðæt, ðət /

A1
  • adjecitve
  • The person or thing being talked about
  • Used to identify something both the speakers know
  • adverb
  • Used to reinforce adjectives and adverbs
  • To such a degree
  • conjunction
  • Used to connect a noun clause
  • Used to introduce an adverbial clause
  • Used to introduce a noun clause
  • determiner
  • Used as a noun to refer to something
  • pronoun
  • Referring an object far away
  • Used to refer to the relative pronoun ‘which’

what

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US / wɒt /

UK / hwɑt, hwʌt, wɔt, wʌt,hwət, wət /

A1
  • pronoun
  • Thing or things that; the same kind as
  • Used to emphasize something you are about to say
  • adjecitve
  • Used to refer to a particular amount, or number
  • Used to place emphasis on a particular quality
  • adverb
  • To a certain degree
  • determiner
  • Question words used for asking for information
  • exclamation
  • Used to express excitement, shock, or surprise
  • Used to ask people to repeat something they said

colour

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US / ˈkʌlə(r) /

UK / ˈkʌlɚ /

A1
  • noun
  • Quality of things you can see, e.g. red, blue
  • Pink or red in your face, e.g. after being ill
  • The shade of someone's skin e.g. black, or yellow
  • verb
  • To change or affect someone's opinion
  • To make something colorful using colored pencils

down

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US / daʊn /

UK / daʊn /

A1
  • adjecitve
  • Being sad, sick, or unhappy
  • Not operating, working, or functioning as expected
  • adverb
  • In a sitting or lying position
  • Towards or on the ground, floor, or bottom
  • Written or copied onto a piece of paper or book
  • noun
  • A period of play in American Football
  • The soft, smooth hairs that cover a bird's body
  • preposition
  • Along something's path, course, or direction
  • Going from a higher position to a lower position
  • verb
  • To eat or drink very quickly and without stopping

fire

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US / 'faɪə(r) /

UK / faɪr /

A1
  • noun
  • Heat and the flame produced when burning
  • Intense energy for or about something
  • verb
  • To apply heat to something to make it hard
  • To make a person leave their job; dismiss
  • To shoot a gun or weapon
  • To launch something into the sky, e.g. a rocket
  • To start working on something e.g. a project

glass

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US / ɡlɑ:s /

UK / ɡlæs /

A1
  • adjecitve
  • Being made of glass
  • noun
  • Clear hard container used for drinking
  • A lens for eyewear
  • Hard see-through material used for making windows

slowly

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US / ˈsləʊli /

UK / ˈsloʊli /

A1
  • adverb
  • In an unhurried or not speedy manner

then

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US / ðen /

UK / ðɛn /

A1
  • adverb
  • A time that is not now
  • Following another thing in time or arrangement
  • Following on reasonably from what was just stated
  • At that time, not now

get

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US / ɡet /

UK / ɡɛt /

A1
  • verb
  • To become affected by illness or disease
  • To begin to feel or understand an emotion or idea
  • To send or bring someone or something home, etc.
  • To go somewhere to obtain something
  • To (cause to) do a particular thing
  • To obtain, receive or be given something
  • To currently have
  • To prepare for use
  • To understand something being said or read

seconds

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US / 'sekəndz /

UK / 'sekəndz /

A1
  • other
  • Units of time; one sixtieth of a minute
  • Short periods of time you wait for someone
  • verb
  • To agree to support a proposal at a meeting

house

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US / haʊs /

UK / haʊs /

A1
  • noun
  • Place where a specific activity or business occurs
  • Building in which a family, person lives
  • verb
  • To give someone a place to live
  • To contain or store something

touch

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US / tʌtʃ /

UK / tʌtʃ /

A1
  • noun
  • Certain way of doing that makes something special
  • A small amount of something
  • Feeling of a surface
  • verb
  • To affect feelings, especially by causing sympathy
  • To be next to each other with no space between
  • To get involved with (used in negative)
  • To feel an object with your fingers, etc.

bang

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US / bæŋ /

UK / bæŋ /

A2
  • noun
  • Sudden loud noise, as when a bomb explodes
  • A loud noise
  • verb
  • To strike something loudly or forcefully

energy

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US / 'enədʒɪ /

UK / ˈɛnədʒi /

A2
  • noun
  • Physical or mental strength

factory

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US / ˈfæktri /

UK / ˈfæktəri /

A2
  • noun
  • Building where things are made

mix

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US / mɪks /

UK / mɪks /

A2
  • noun
  • A combination of more than two things
  • verb
  • To combine two or more things to make one
  • To meet and get along with others, e.g. at a party

oxygen

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US / 'ɒksɪdʒən /

UK / ˈɑksɪdʒən /

B1
  • noun
  • A gas in the air that we need to breathe

interesting

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US / ˈɪntrəstɪŋ /

UK / ˈɪntrɪstɪŋ, -tərɪstɪŋ, -təˌrɛstɪŋ /

A1
  • adjecitve
  • Taking your attention; making you want to know
  • verb
  • To make someone want to know about something
  • To persuade to do, become involved with something

example

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US / ɪgˈzɑ:mpl /

UK / ɪɡˈzæmpəl /

A1
  • noun
  • Thing, person which represents a category

happen

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US / 'hæpən /

UK / ˈhæpən /

A1
  • verb
  • To take place or occur

same

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US / seɪm /

UK / sem /

A1
  • adjecitve
  • Being equal in quality and amount
  • Identical; not different
  • Not changing; constant

food

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US / fu:d /

UK / fud /

A1
  • noun
  • What people and animals eat to live
  • Things taken in by plants to maintain life
  • A particular style or type of cooking, e.g. Asian

not

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US / nɒt /

UK / nɑt /

A1
  • adverb
  • Word indicating the negative
  • (Used to form the negative of verbs)

quite

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US / kwaɪt /

UK / kwaɪt /

A1
  • adverb
  • Not very; fairly
  • Very; In a complete or total manner

yours

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US / jɔ:z /

UK / jʊrz, jɔrz, jorz /

A1
  • pronoun
  • Something the other person has

whole

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US / həul /

UK / hol /

A1
  • adjecitve
  • Complete or full; all of
  • Being in a good condition
  • noun
  • Complete amount or sum; total

scale

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US / skeɪl /

UK / skel /

A2
  • noun
  • Size, level, or amount when compared
  • Small hard plates that cover the body of fish
  • Device that is used to weigh a person or thing
  • Range of numbers from the lowest to the highest
  • Dimensions or size of something
  • verb
  • To change the size of but keep the proportions
  • To climb something large (e.g. a mountain)
  • To remove the scales of a fish

friend

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US / frend /

UK / frɛnd /

A1
  • noun
  • Person who you like and enjoy being with

now

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US / naʊ /

UK / naʊ /

A1
  • adverb
  • At the present time or moment
  • Right away or in the next possible moment
  • Used to refer to something that just happened
  • Time between the present and a moment in the past
  • conjunction
  • Resulting from or because of something

can

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US / kæn /

UK / kən,kæn /

A1
  • noun
  • A metal container for storing food
  • other
  • Able to; have the skill to; have the time to
  • verb
  • To have permission to
  • To be possible to do
  • To preserve food by sealing it in a metal container

compare

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US / kəm'peə(r) /

UK / kəmˈpɛr /

A1
  • verb
  • To consider how similar and different things are

really

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US / ˈri:əli /

UK / ˈriəˌli, ˈrili /

A1
  • adverb
  • Used to stress something that is said; definitely
  • In a true or accurate manner
  • Very

sum

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US / sʌm /

UK / sʌm /

A2
  • noun
  • Amount when all is added together; total
  • verb
  • To add two or more numbers together; total

thin

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US / θɪn /

UK / θɪn /

A1
  • adjecitve
  • Flowing with ease; with a high percentage of water
  • (Of air) having little oxygen
  • Being or growing far apart in small amounts
  • Not thick; not wide in size
  • Having little flesh or fat on the body
  • Being weak or useless
  • verb
  • To make flow more easily by adding water or liquid

video

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US / 'vɪdɪəʊ /

UK / ˈvɪdiˌo /

A2
  • adjecitve
  • Of a moving film, with sound
  • noun
  • Recording capturing action with sound
  • verb
  • To make a moving film of, with sound

but

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US / bət /

UK / bʌt,bət /

A1
  • conjunction
  • Used before you say something different, opposite

demonstrate

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US / 'demənstreɪt /

UK / ˈdɛmənˌstret /

A2
  • verb
  • To display a feeling or ability openly
  • To protest about something often as a group
  • To prove or make clear by reasoning or evidence
  • To show how something works (e.g. product)

give

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US / ɡɪv /

UK / ɡɪv /

A1
  • noun
  • Degree of flexibility in something, a material
  • verb
  • To hand over or present something to someone
  • To cause someone to have or experience something

illustrate

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US / ˈɪləstreɪt /

UK / ˈɪləˌstret, ɪˈlʌsˌtret /

A2
  • verb
  • To supply pictures to go along with words
  • To be an example that explains or proves something

slake

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US / sleɪk /

UK / slek /

C2
  • verb
  • To satisfy (e.g. your thirst by drinking)

blow

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US / bləʊ /

UK / blo /

A2
  • noun
  • Something that causes you difficulty or sadness
  • Act of making air come out of your mouth
  • A hit or strike from an object
  • verb
  • To move something using air
  • To make air come quickly out of your mouth
  • To clear something by forcing air through it

hand

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US / hænd /

UK / hænd /

A1
  • noun
  • Cards given to a player in a card game
  • Piece of a clock that points to the time
  • Someone who performs physical tasks or work
  • Body part at the end of a person's arm
  • Help for someone performing a particular action
  • Condition of having power or influence
  • Member of the crew of a ship
  • verb
  • To give something to someone personally

kitchen

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US / ˈkɪtʃɪn /

UK / ˈkɪtʃən /

A2
  • noun
  • Place where food is cooked

have

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US / həv /

UK / hæv /

A1
  • verb
  • To drink, smoke, eat or use something
  • To experience the effects of something
  • To organize an event, or join in an activity
  • To own, possess, or hold something
  • To cause to happen or produce a particular effect

salt

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US / sɔ:lt /

UK / sɔlt /

A2
  • adjecitve
  • Being preserved or seasoned with salt
  • noun
  • Natural white crystal used to flavor food
  • verb
  • To add salt to food in order to improve its taste
  • To add salt to ice in order to melt it
  • To preserve food by adding salt

air

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US / eə(r) /

UK / er /

A1
  • noun
  • Mixture of gases around the earth that we breathe
  • A person's manner intended to impress others
  • verb
  • To expose to the outside, to dry or freshen
  • To broadcast a TV or radio show
  • To open a subject to discussion and debate

break

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US / breɪk /

UK / brek /

A1
  • noun
  • Time you stop an activity before continuing
  • End of a relationship
  • An escape from a place such as a jail
  • (Lucky) advantage or benefit from something
  • Find a solution or answer to a problem or crime
  • Change in the weather
  • verb
  • To create a new record e.g. running the 100m dash
  • To form a crack in something
  • To burst or become damaged
  • To end a relationship
  • To escape from a place such as a jail
  • To train a wild animal e.g. a horse
  • To separate into pieces by force, or by dropping
  • To act against a law, rule, or promise
  • To become known suddenly, as in the news
  • To not do what you promised e.g. not keep promises
  • To solve a crime, or answer a problem
  • To stop functioning properly
  • To suddenly start, open or commence
  • To change in pitch suddenly, as in a voice
  • To fall on the shore, as in waves
  • To begin or change suddenly; the dawn or weather
  • To defeat by causing the person to lose their will

increase

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US / ɪn'kri:s /

UK / ɪnˈkris /

A1
  • noun
  • Fact of increasing; amount something grows by
  • verb
  • To make or become larger in size or amount

thermocouple

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US / ˈθɜːməʊkʌp(ə)l /

UK / ˈθɜːrməˌkʌpl /

A1
  • noun
  • Kind of thermometer consisting of two wires of different metals that are joined at both ends; one ju

weak

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US / wi:k /

UK / wik /

A1
  • adjecitve
  • Not having a strong character
  • Less valuable compared to money of other countries
  • Ineffective; unconvincing; not strong
  • Having little power or ability
  • Not having the necessary or proper amount
  • Having little power; not strong; easy to break
  • (Of a drink) having lots of water and little taste

process

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US / prə'ses /

UK / ˈprɑsˌɛs, ˈproˌsɛs /

A2
  • noun
  • Dealing with official forms in the way required
  • Set of changes that occur slowly and naturally
  • verb
  • To organize and use data in a computer
  • To deal with official forms in the way required
  • To prepare by treating something in a certain way
  • To adopt a set of actions that produce a result
  • To convert by putting something through a machine

mixed

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US / mɪkst /

UK / mɪkst /

A2
  • verb
  • To combine two or more things to make one
  • To meet and get along with others, e.g. at a party

with

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US / wɪð /

UK / wɪð, wɪθ /

A1
  • preposition
  • As an employee of a certain company
  • Against something or someone
  • By using something as a means
  • Due to; because of
  • Including
  • Possessing as a feature
  • Related to
  • (Of the manner/attitude by which you do something)
  • Used to express that people or things are together

know

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US / nəʊ /

UK / noʊ /

A1
  • verb
  • To be familiar with a person or place, thing
  • To feel sure or be convinced about something
  • To discover or be aware of something
  • To be able to distinguish
  • To have knowledge of things

moment

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US / 'məʊmənt /

UK / 'moʊmənt /

A1
  • noun
  • Very short or brief period of time
  • A particular period in time

away

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US / ə'weɪ /

UK / əˈwe /

A1
  • adjecitve
  • Not present
  • adverb
  • Disappear completely
  • Doing something with a lot of energy
  • Not here; far from here; in a different direction
  • To a different area, location

see

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US / si: /

UK / si /

A1
  • verb
  • To go on a date with someone
  • To predict whether something is, or will be true
  • To understand what someone says
  • To use your eyes to look at something
  • To visit a place often for sightseeing or pleasure
  • To visit or meet with someone
  • To find out by waiting or looking
  • To watch (a game, movie or TV show)

atom

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US / 'ætəm /

UK / ˈætəm /

B1
  • noun
  • Smallest bit that matter can be broken down into

between

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US / bɪˈtwi:n /

UK / bɪˈtwin /

A1
  • preposition
  • From one person, thing, or place, to another
  • In the space that separates two objects
  • Among two or more people who share something

they

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US / ðeɪ /

UK / ðe /

A1
  • pronoun
  • Two or more people, animals, or things

volume

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US / ˈvɒlju:m /

UK / ˈvɑljum, -jəm /

A2
  • noun
  • Number or amount of something e.g. sales
  • Amount of space that something takes up
  • One book that is part of a set of books
  • Level of sound produced by radio or television

very

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US / 'verɪ /

UK / ˈvɛri /

A1
  • adjecitve
  • Concerning a large degree or amount
  • adverb
  • A lot; much; many
  • Used to stress or emphasize a noun

all

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US / ɔ:l /

UK / ɔl /

A1
  • adverb
  • Completely; totally
  • determiner
  • Being every one of something
  • pronoun
  • 100% of something; the complete amount

fast

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US / fɑ:st /

UK / fæst /

A1
  • adjecitve
  • In a way that is difficult to move or change
  • Moving or able to move quickly
  • Showing time that is later than the actual time
  • adverb
  • With a great deal of speed
  • noun
  • Period of time when a person chooses not to eat
  • verb
  • To refuse food for a long time

produce

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US / prə'dju:s /

UK / prəˈdus, -ˈdjus, pro- /

A1
  • noun
  • Fresh foods such as fruits and vegetables
  • verb
  • To grow something naturally
  • To make something appear
  • To manufacture something using machines
  • To control the making a movie or television show

proportionally

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US / prə'pɔ:ʃənlɪ /

UK / prə'pɔ:ʃənlɪ /

B1
  • adverb
  • So that the ratio of two quantities is constant

their

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US / ðɛː /

UK / ðer /

A1
  • determiner
  • Belonging to them

way

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US / weɪ /

UK / we /

A1
  • adverb
  • Used to emphasize the amount of something
  • noun
  • Particular aspect of something being thought about
  • One of various choices that could be made
  • Particular existing condition or state
  • (Often long) distance or length of time
  • How something is done
  • Route to go to a place
  • Small street
  • Usual behavior, emotions or habits of someone

change

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US / tʃeɪndʒ /

UK / tʃendʒ /

A1
  • noun
  • Exchange of one set of clothes for another
  • Money in the form of coins instead of paper
  • Money returned after giving too much
  • Act of making or becoming something else
  • verb
  • To exchange one set of clothes for another
  • To exchange one kind of money for another
  • To replace something with another thing
  • To make or become something else
  • To go from one train, bus, etc. and go to another

calcium

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US / 'kælsɪəm /

UK / ˈkælsiəm /

C2
  • noun
  • A substance important for making bones and teeth

heating

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US / ˈhiːtɪŋ /

UK / ˈhiːtɪŋ /

A2
  • noun
  • System that provides warmth to a house or building
  • verb
  • To make hot or hotter

show

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US / ʃəʊ /

UK / ʃo /

A1
  • noun
  • False display of love, emotion or action
  • An event for displaying or promoting goods
  • Play, opera or theater production
  • Presentation that is broadcast on TV or radio
  • verb
  • To be easily seen or displayed
  • To display your emotions or feelings
  • To let someone see something; display
  • To explain or teach how something is done
  • To lead someone somewhere; point them to something
  • To prove something to be true, correct
  • To reveal or allow something to be seen

beaker

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US / ˈbi:kə(r) /

UK / ˈbikɚ /

B2
  • noun
  • Flat-bottomed jar made of glass or plastic

look

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US / lʊk /

UK / lʊk /

A1
  • noun
  • Person's beauty or physical attractiveness
  • Particular style of dress, clothes, or appearance
  • The way someone, something appears to be
  • Act of searching for or examining something
  • verb
  • To appear to be; seem

pretty

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US / 'prɪtɪ /

UK / ˈprɪti /

A1
  • adjecitve
  • Being attractive to the eye in a simple way
  • adverb
  • Very; to a great degree

add

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US / æd /

UK / æd /

A1
  • verb
  • To include as well
  • To put two things or numbers together, e.g. 2+2

fat

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US / fæt /

UK / fæt /

A1
  • adjecitve
  • Having too much weight for the body size
  • Bringing or having a large amount of money
  • noun
  • Amount beyond what is usual or necessary
  • Oily part of meat

gentle

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US / 'dʒentl /

UK / ˈdʒɛntl /

A2
  • adjecitve
  • Kind and quiet in nature; not harsh or violent

spectacular

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US / spekˈtækjələ(r) /

UK / spɛkˈtækjəlɚ /

B1
  • adjecitve
  • Impressive or out of the ordinary

room

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US / ru:m /

UK / rum, rʊm /

A1
  • noun
  • All of the people inside a particular room
  • Part of building enclosed by walls, e.g. kitchen
  • Opportunity to exist, happen, or be true
  • verb
  • To share a home with someone

take

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US / teɪk /

UK / tek /

A1
  • noun
  • Filming of a single scene for TV or the movies
  • verb
  • To accept something that is offered
  • To use a method of traveling, e.g. a bus or train
  • To use a camera to make (a photo)
  • To pick up something and go away with it
  • To study a subject in school
  • To attempt to pass (an exam)
  • To require a certain amount of time, money, space

less

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US / les /

UK / lɛs /

A1
  • adjecitve
  • Smaller in amount or degree
  • adverb
  • To a smaller degree
  • noun
  • A smaller amount
  • preposition
  • With the subtraction of

crisp

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US / krɪsp /

UK / krɪsp /

B1
  • adjecitve
  • (Of weather) chilly; a little cold
  • noun
  • Thin fried slices of potatoes, eaten as a snack
  • verb
  • To make or become dry and crisp, as with heat

oxide

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US / ˈɒksaɪd /

UK / ˈɑ:ksaɪd /

B2
  • noun
  • Compound from combining oxygen with a chemical

this

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US / ðɪs /

UK / ðɪs /

A1
  • adjecitve
  • Used to indicate something already been discussed
  • Used to indicate something happening around now
  • adverb
  • An indication by a physical motion or gesture
  • A specific amount of
  • determiner
  • Person, thing, or idea near you
  • pronoun
  • Person, thing that has already been discussed

word

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US / wɜ:d /

UK / wɚd /

A1
  • noun
  • Unit of language that has a meaning
  • Promise
  • Short remark or piece of information
  • verb
  • To express something by choosing particular words

big

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US / bɪɡ /

UK / bɪɡ /

A1
  • adjecitve
  • Popular
  • Serious
  • Large

cupboard

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US / ˈkʌbəd /

UK / ˈkʌbərd /

A2
  • noun
  • Piece of furniture used for storage

let

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US / let /

UK / lɛt /

A1
  • verb
  • To allow someone to do something
  • Introducing a suggestion to do something together
  • To rent a house, etc. to others

easily

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US / ˈi:zəli /

UK / ˈizəli /

A1
  • adverb
  • Clearly; without doubt; certainly
  • Without difficulty

rate

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US / reɪt /

UK / ret /

A1
  • noun
  • Current price or cost of something
  • Speed or frequency of events over time
  • verb
  • To assess something or consider its qualities

the

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US / ðə /

UK / ðə /

A1
  • article
  • Used to refer to something already mentioned
  • Used to show there is only one of something
  • determiner
  • Used to describe all of a family

chemist

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US / ˈkemɪst /

UK / ˈkɛmɪst /

B1
  • noun
  • Person who sells medicines; drug store
  • Person who studies or does research in chemistry

kind

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US / kaɪnd /

UK / kaɪnd /

A1
  • adjecitve
  • In a caring and helpful manner
  • friendly and considerate
  • noun
  • One type of thing

hydroxide

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US / haɪˈdrɒksaɪd /

UK / haɪˈdrɑ:ksaɪd /

A1
  • noun
  • Chemical compound containing the hydroxyl group

you

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US / jʊ /

UK / ju /

A1
  • pronoun
  • Person someone is speaking or writing to
  • Person or people in general

other

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US / 'ʌðə(r) /

UK / ˈʌðər /

A1
  • adjecitve
  • A thing different from that mentioned
  • determiner
  • (Something) else; not the first (one)
  • pronoun
  • Being the one and only thing of that category

one

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US / wʌn /

UK / wʌn /

A1
  • pronoun
  • You; we; people in general; someone
  • The thing or person previously referred to
  • adjecitve
  • Used to refer to people generally
  • Being a strong example of (something mentioned)
  • number
  • Number 1

open

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US / 'əʊpən /

UK / ˈopən /

A1
  • adjecitve
  • Available for use; accessible
  • Not being hidden; available for others to see
  • Being available for customers to enter or use
  • Allowing everyone to use or take part in
  • Not secret anymore
  • Not closed or shut
  • Willing to accept new ideas and thoughts
  • noun
  • Name for a tennis or golf competition
  • verb
  • To make accessible or able to be used, e.g. road
  • To start the activities or services of a business
  • To make a space or hole appear in something
  • To move or change so that it is no longer closed
  • To start something, e.g. a new business

than

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US / ðən /

UK / ðən /

A1
  • conjunction
  • Used to compare two things that are not equal

term

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US / tɜ:m /

UK / tɚm /

A1
  • noun
  • Conditions applying to an agreement, contract
  • Length of time something is expected to happen
  • Fixed period of weeks for learning at school
  • The (precise) name given to something
  • verb
  • To call; give a name to

surface

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US / 'sɜ:fɪs /

UK / ˈsɚfəs /

A2
  • adjecitve
  • Of the top layer; not deep or meaningful
  • noun
  • Top layer of the ground or of water
  • Nature or emotions that show, but may not be true
  • Outside or upper layer of something
  • verb
  • To give (road) a top layer
  • To appear after being hidden, unseen, or unknown
  • To come to the top of something; emerge
  • To come to the top level of water, mud, etc.

chemical

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US / ˈkemɪkl /

UK / ˈkɛmɪkəl /

A2
  • adjecitve
  • Made of various elements
  • noun
  • Basic substance produced by mixing elements

half

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US / hɑ:f /

UK / hæf, hɑf /

A1
  • adjecitve
  • Not complete
  • adverb
  • Partly; somewhat
  • noun
  • One of two equal periods of game time in a sport
  • The part you get when one is divided into two;

truly

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US / 'tru:lɪ /

UK / ˈtruli /

A2
  • adverb
  • In accordance with truth, fact or reality; really

body

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US / ˈbɒd.i /

UK / ˈbɑdi /

A1
  • noun
  • An object distinct from other objects
  • A group of people involved in an activity together
  • Main part of something
  • A person's physical self

make

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US / meɪk /

UK / mek /

A1
  • noun
  • Product made by a particular company; brand
  • verb
  • To arrange or prepare something e.g. dinner
  • To get to (a place) on time
  • To gain the status of (teacher, lawyer, etc.)
  • To create something by putting things together
  • To earn a certain amount of money at a job
  • To cause or force a person to do something
  • To cause something to happen or be formed

ones

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US / wʌnz /

UK / wʌnz /

A1
  • number
  • Number 1, a single person or thing

run

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US / rʌn /

UK / rʌn /

A1
  • noun
  • Journey between two places made by ship or car
  • Series of similar things or successes and failures
  • Act of running; exercise of running
  • verb
  • To depart or travel according to a schedule
  • To cause an animal to move in a certain direction
  • (Of an engine) to be operating
  • To start or use a computer program
  • To flow in a certain direction, like a liquid
  • To manage or operate a business
  • To operate or drive something
  • (Of a road) to go from one place to another
  • To move your legs faster than walking
  • Subtitles section
  • The word is exothermic.
  • Exothermic is actually a reaction or a process that gives out a lot of thermal energy.
  • An exothermic reaction or process is one that gives out heat.
  • So if you mix the chemicals very, very slowly, it all just gets pleasantly warm.
  • If you mix them too fast, there's a big bang.
  • And there are many, many, many examples where people have mixed things too fast and either had a small bang or blown up their whole factory.
  • So to illustrate that, what I thought is actually to do a reaction that demonstrates a truly exothermic process.
  • So rather than doing a reaction that generates a lot of, I don't know, colour change, sound in terms of an explosion, there are other videos that show that really well.
  • So this exothermic process, while it's not a spectacular sum, hopefully you should see the temperature increase dramatically.
  • The rate of reaction when you're doing an exothermic reaction is very important.
  • And what is really important is that if you have a small flask like this one, the heat can get out quite easily because there's just quite a lot of surface area.
  • But then if you take something really big, much bigger, the surface area is proportionally smaller, so the heat can't get out so easily.
  • So when chemists scale up, make things on a larger scale, that's when things can go wrong.
  • It's just like on a cold day, if you're thin, you wrap up really warm to keep out the cold.
  • But your really fat friend is running around in a t-shirt saying it's too hot and sweating like a pig because the fat friend's surface area is much smaller compared to the volume than yours is.
  • So what we have here is something called calcium oxide.
  • You can see it's in an interesting kind of container, not a glass container, and it says to open it carefully.
  • So if I pop that there.
  • Exothermic reactions are quite safe.
  • Just feel your body, it's warm.
  • It's warm because it's an exothermic reaction.
  • The food that you are eating, the oil from your crisps is reacting with oxygen in the air and letting out heat in a gentle way.
  • But if you set fire to the oil in the kitchen, you can burn the house down because the reaction is going to higher temperature and so much faster.
  • So calcium oxide looks pretty much like any other form of calcium salt.
  • It's a white solid.
  • So what we'll do is put some of it in here.
  • OK, so we've got about half a beaker's worth of calcium oxide there, so approximately about 100 grams.
  • So the thermocouple at the moment is at room temperature, and so room temperature is about 15.5 degrees C. And even though it's inside the calcium oxide, the temperature is about the same as the fume cupboard in the room.
  • So what we're going to do now is add some distilled water to the beaker and we'll see what happens to the thermocouple.
  • So immediately you're seeing the increase in temperature.
  • So it's gone from 15, shot all the way up now to 45, and it's still going strong.
  • When a chemical reaction occurs, you have to start the reaction to break bonds between atoms.
  • Then they react, and they make new bonds, and you get some energy back.
  • If the energy you get back is more than the energy you put in, it gets hotter.
  • So the reaction goes faster.
  • It releases more energy, and it runs away.
  • It goes faster and faster and faster.
  • But if, on the other hand, you are breaking strong bonds and making weak ones, less energy comes out than you put in, and you have to keep on heating it, or the reaction just stops.
  • Within seconds, it's gone from 15.5 degrees C to over 100.
  • So with this beaker, I'm definitely not going to touch it because it's going to be really hot.
  • So this reaction is known as the slaking of quicklime.
  • So it's calcium oxide and water producing calcium hydroxide.