Introducing Chemistry
States matter
| Word | Pronunciation | Meaning |
| dense | Something which is heavy for its volume. | |
| flow | Move. | |
| gas | Something that does not have a fixed shape or volume, and is easy to squash. | |
| liquid | lick-wid | Something with a fixed volume but no fixed shape. |
| property | A description of how a material behaves and what it is like. Hardness is a property of some solids. | |
| solid | Something with a fixed shape and volume. | |
| states of matter | There are three different forms which a substance can be in; solid, liquid or gas. These are the three states of matter. |
In theory
| Word | Pronunciation | Meaning |
| data | Results of an experiment. | |
| observation | What you see happening in an experiment. | |
| prediction | What you think will happen in an experiment. | |
| theory | thear-ree | An idea about why things work the way they do. Scientists use their imaginations to come up with a theory. |
| bonds | Forces holding particles together. | |
| particles | part-ick-als | The tiny pieces that everything is made out of. |
| vibrate | Move backwards and forwards. | |
| diffusion | When particles mix with each other without anything moving them | |
| pressure | presh-ur | The force caused by particles hitting a certain area. |
| vacuum | vack-yoom | A completely empty space. |
The solution is clear/Melting away
| Word | Pronunciation | Meaning |
| dissolving | diss-olv-ing | When a solid splits up and mixes with a liquid to make a solution. |
| filtering | Separating things that have not dissolved from a liquid. The liquid is passed through a filter to do this. | |
| insoluble | A solid that will not dissolve. | |
| mixture | A lot of different things jumbled up together. | |
| soluble | sol-you-bull | A solid that can dissolve in a liquid. Salt is soluble in water. |
| solute | The solid that has dissolved in a liquid to make a solution. | |
| solution | sol-oo-shun | When a solid has dissolved in a liquid. |
| solvent | The liquid that has dissolved a solid to make a solution. | |
| transparent | Another word for see-through. |
Salt of the Earth
| Word | Pronunciation | Meaning |
| brine | A solution of common salt and water. | |
| common salt | A chemical we use to make things taste ‘salty’. | |
| evaporation | ev-app-or-ay-shun | A liquid turning into a gas. |
| salts | Chemicals from rocks that have dissolved in water. |
Still water
| Word | Pronunciation | Meaning |
| condensing | A gas turning into a liquid. | |
| distillation | dist-till-ay-shun | The process of separating a liquid from a solution by evaporating the liquid and then condensing it. |
| pure | A substance that does not have anything else in it. | |
| steam | Water as a gas. Also called water vapour. | |
| still | The apparatus used for distillation. | |
| water vapour | vay-per | Water as a gas. Also called steam. |
Dyeing for juice
| Word | Pronunciation | Meaning |
| chromatogram | krow-mat-O-gram | The dried piece of paper produced by chromatography. |
| chromatography | krow-mat-og-graph-ee | Separating dissolved solids from one another. The solids are usually coloured. |
A soluble problem
| Word | Pronunciation | Meaning |
| saturated | A solution that contains as much dissolved solid as it possibly can. | |
| solubility | sol-you-bill-ity | The amount of a solid that will dissolve in 100g of a liquid. |
| variable | vair-ri-able | A factor in an experiment that can change. |
Tangy tastes
| Word | Pronunciation | Meaning |
| acetic acid | a-see-tick | The old name for ethanoic acid. It is the acid in vinegar. |
| acid | A substance that turns litmus red. It has a pH of less than 7. | |
| ascorbic acid | a-score-bick | Chemical name for vitamin C. |
| citric acid | sit-rick | The acid in citrus fruits. |
| ethanoic acid | eth-an-know-ic | The acid in vinegar. |
Diamonds are for safety
| Word | Pronunciation | Meaning |
| corrosive | cor-row-sive | Substances that attack metals, stonework and skin are called corrosive. |
| harmful | Another word for irritant. | |
| hydrochloric acid | A common acid that is also found in your stomach. | |
| irritant | Something that irritates the skin and eyes. | |
| nitric acid | A common acid. | |
| sulphuric acid | A common acid. Used in car batteries. |
In the red
| Word | Pronunciation | Meaning |
| alkali | alk-al-lie | Substance that turns litmus blue. Has a pH of more than 7. |
| indicator | ind-ic-ay-ter | A dye that will change colour in acids and alkalis. |
| litmus | A simple kind of indicator. It turns red in acids and blue in alkalis. | |
| neutral | Substance that is not an acid or an alkali. Has a pH of 7. |
Mixing a rainbow
| Word | Pronunciation | Meaning |
| antacid | ant-ass-id | A medicine containing an alkali used to cancel out some of the acid in the stomach to treat heartburn. |
| pH scale | A numbered scale from 1–14 showing the strengths of acids and alkalis. Numbers below 7 are acids. Numbers above 7 are alkalis. pH 7 is neutral. | |
| universal indicator | A mixture of indicators giving a different colour depending on how weak or strong an acid or alkali is. |
Finding the balance
| Word | Pronunciation | Meaning |
| dilute | die-loot | We dilute a solution by adding more of the solvent to it. |
| neutralisation | When something is neutralised. | |
| neutralise | When an acid is added to a base (or alkali) a neutral substance is produced. |