| Question | Answer |
|---|---|
| What is the name of a process where gases are converted to liquids? | Condensing |
| What state of matter is produced as a result of melting? | Liquid |
| Which state of matter can change its shape and its volume? | Gas |
| Which state of matter has the smallest spaces between its particles | Solid |
| What happens to all matter when it is heated? | It expands |
| Everyday example of expansion/contraction? | Water in pipes in winter can freeze and expand causing them to burst. |
| What are the four signs of chemical reaction? | Colour change, Gas being formed, Solid being formed, a change in energy |
| What is always formed by a chemical reaction? | A new product |
| What is meant by a term Non Newtonian fluid? | Non Newtonian fluid is a substance that sometimes behaves like a solid and sometimes like a liquid |
| Which is a faster chemical reaction: iron rusting or a firework going off? | A firework going off is a faster chemical reaction. |
| Is salt dissolving in water a chemical or a physical reaction? | Salt dissolving in water is a physical reaction. |
| Why is salt dissolving in water not a chemical reaction? | There is no new product formed. Water can be evaporated and salt would remain behind. |
| What are three ways of speeding up a chemical reaction? | Increase concentration, decrease particle size and increase temperature |
| What are three ways of slowing down a chemical reaction? | Decrease concentration, increase particle size and decrease temperature |
| What name is given to a substance that can change its shape but not its volume? | Substance that can change its shape but not its volume is called a liquid. |
| What kind or reactions are breaking glass, ice melting, paint drying, water boiling? | These are physical reactions |
| What kind of reactions are frying an egg and gas explosion? | These are chemical reactions |
| Which is the only sign of chemical reaction that is present in every chemical reaction? | A change in energy |
| What instrument do we use to measure temperature? | A thermometer. |
| Name two examples of Non Newtonian liquid | Custard and mayonnaise. |
| What are the three states of matter? | Solid, liquid and gas |
| How are particles arranged in a solid? | The particles are very close together |
| What happens at the melting point of a substance? | A solid changes into a liquid |
| When a solid expands what happens to its particles? | They move further appart |
| All liquids have a fixed volume and take the shape of their container. True or False | True |
| Is burning of petrol a physical reaction? | No burning petrol is a chemical reaction |
| A bee sting is acidic. Which would neutralise it baking soda or alcohol? | Baking soda |
| Which solution is more concentrated: 6g of salt + 60 ml of water or 10g of salt + 60 ml of water | 10g of salt + 60 ml of water is more concentrated |
| If water is added to acid the acid becomes less acidic and its pH goes down. True or false? | False, it becomes less acidic and its pH goes UP! |
| What is meant by a term catalyst? | A substance that speeds up a reaction and is not used up in the process |
| What is a name for biological catalyst found in living things? | An enzyme |
| How would you measure a pH of a hydrochloric acid solution? | Add a drop of universal indicator and check the colour of the solution against a pH colour chart. |
| What are the two substances produced when you add potassium hydroxide to hydrochloric acid? | potassium chloride and water |
| What are the two factors needed for rusting to take place? | Oxygen and moisture (water) are present |
| State one way to protect iron from rusting | Use paint |
| Iron rusts faster if it is put in sea water. Why is that? | Sea water contains salt which speeds up the rate of rusting. |
| Out of: aluminium, copper, zinc and potassium which one would produce bubbles of hydrogen gas if put in water? | Potassium |
