Chemical Reactions Questions

Question 1

Identify the reactants and products and write out the word equations for the following
a. Propane burns in air to produce carbon dioxide and water vapour.

Answer 1

Reactants: propane and oxygen
Products: carbon dioxide and water
Word equation:
Propane + oxygen  carbon dioxide + water

Question 2

Hydrochloric acid reacts with magnesium carbonate to produce carbon dioxide gas,
magnesium chloride solution and water.

Answer 2

Reactants: Hydrochloric acid and magnesium carbonate
Products: carbon dioxide, magnesium chloride and water
Word equation: Hydrochloric acid + magnesium carbonate  carbon dioxide + magnesium chloride + water

Question 3

Water reacts violently with sodium metal to create sodium oxide and hydrogen gas.

Answer 3

Reactants: water and sodium
Products: sodium oxide and hydrogen
Equation: water + sodium  sodium oxide + hydrogen

Question 4

Define endothermic and exothermic reactions and give 2 examples of each type of reaction.

Answer 4

Exothermic are reactions that release energy in the form of heat sound or light. Examples include a
candle burning. Endothermic are reactions that absorb energy from their surroundings. Examples include photosynthesis.

Question 5

Explain the differences between combustion and incomplete combustion.

Answer 5

Complete combustion reactions occur when there is an unlimited supply of oxygen. Fuel reacts with
oxygen and carbon dioxide is produced along with water. Incomplete combustion is when oxygen
is limited and carbon monoxide is produced.

Question 6

Write out the general word equation for the combustion of methane.

Answer 6

Methane + oxygen  carbon dioxide + water

Question 7

State the reactant always needed for combustion reactions to occur.

Answer 7

Oxygen

Question 8

Write out the general equation for respiration and photosynthesis. Identify both the products
and reactants for each of these reactions.