Question

2. What is combination reaction? State one example giving balanced chemical equation for the
reaction.
3. What does one mean by exothermic and endothermic reactions? Give examples.
What do you observe when calcium oxide is added to water? Explain
5. 1) Explain the term "rancidity".
Name the type of chemical reaction responsible for causing rancidity and define it.
ii) Write three methods for preventing rancidity of food.​

Answer 1

Explanation:

Expressed in a chemical equation: reactants → products + energy. For example: Combustion is exothermic reaction. The chemical reaction between zinc granules and dilute sulphuric acid is exothermic reaction. For example: Magnesium and oxygen combine, when heated, to form magnesium oxide.