chemical reaction

1. Reaction – A process where substances (reactants) are transformed into new substances (products) with different properties.
3. – A reaction in which a substance reacts with oxygen, releasing heat and light (burning).
4. Scale – A scale from 0 to 14 that measures the acidity or alkalinity of a solution (0-6 acidic, 7 neutral, 8-14 basic).
10. – Substances that change color to show the presence of an acid or base (e.g., litmus paper, universal indicator).
11. Change – A change that results in the formation of one or more new substances (e.g., burning, rusting).
14. of Mass – The principle that matter is neither created nor destroyed in a chemical reaction; the mass of reactants equals the mass of products.
15. of Reaction – The speed at which reactants turn into products, affected by temperature, concentration, surface area, and catalysts.
16. – A substance that speeds up a chemical reaction without being used up.
18. Reaction – A reaction where a compound breaks down into simpler substances (e.g., electrolysis of water).
19. – The starting substances in a chemical reaction that undergo change.

2. Reaction – A reaction that absorbs heat energy from the surroundings (e.g., photosynthesis, melting ice).
4. – A solid that forms from a solution during a chemical reaction.
5. – The slow destruction of metals due to reactions with oxygen and water (e.g., rusting).
6. – A reaction where a substance gains oxygen or loses electrons (e.g., rusting of iron).
7. Change – A change that affects the form of a substance but does not create a new substance (e.g., melting, freezing, dissolving).
8. Reaction – A reaction that releases heat energy to the surroundings (e.g., combustion, respiration).
9. (Synthesis) Reaction – A reaction where two or more substances combine to form a new compound.
12. Reaction (Neutralization) – A reaction between an acid and a base to produce a salt and water.
13. Reaction – A reaction where a more reactive element replaces a less reactive element in a compound.
17. – The new substances formed as a result of a chemical reaction.