Chemical changes

3. A solid that forms and separates from a liquid mixture during a chemical reaction.
6. The bubbling and fizzing that occurs when gas is released during a chemical reaction, often seen when an acid reacts with a carbonate.
8. A substance that is formed as a result of a chemical reaction. Products are what you have after the reaction is complete.
9. The amount of a substance (solute) present in a given volume of solution. Higher concentration means more solute is dissolved in the solution.
11. A substance that speeds up a chemical reaction without being consumed or permanently changed by the reaction itself.
12. A substance that starts a chemical reaction. Reactants are what you have before the reaction takes place.
13. To recognise or point out the differences between two or more substances or concepts.

1. Change A change that affects one or more physical properties of a substance but does not change its chemical composition. Examples include changes in state, like melting or boiling.
2. A type of chemical reaction where two or more simple substances combine to form a more complex substance.
4. The process that occurs when reactants undergo a chemical change to form products.
5. Equation A way of representing a chemical reaction using the names of the reactants and products, rather than chemical formulas. For example, "hydrogen + oxygen → water".
7. Change A process where substances combine or break apart to form new substances with different properties. This often involves a change in colour, temperature, or the production of gas.
10. Rate The speed at which a chemical reaction occurs, often measured by how quickly reactants are used up or products are formed.
11. A process or action that makes something different from what it was before.