Three types of chemical reaction | Exit Quiz | Oak National Academy

What does the "+" symbol represent in a chemical equation?

• Plus

• And

• Or

• Equals

Answer explanation

In chemical equations, the "+" symbol means 'and', indicating the combination of reactants.

In an oxidation reaction, what chemical substance does a reactant combine with?

Answer explanation

Oxidation involves a reactant combining with oxygen.

What is produced in a decomposition reaction?

• A single new substance

• Two or more new substances

• An insoluble salt

• Oxygen

Answer explanation

Two or more new substances are produced, as a reactant breaks down in a decomposition reaction.

In a chemical equation the ___ signifies "changes into", indicating the transformation of reactants into products.

Answer explanation

The arrow (→) signifies "changes into", indicating the transformation of reactants into products.

A reaction that forms an insoluble salt when two solutions are mixed is called a ___ reaction.

Answer explanation

This reaction results in an insoluble salt being formed.

Which of the following are oxidation reactions?

• H₂ + O₂ → H₂O

• CaCO₃ → CaO + CO₂

• 2Mg + O₂ → 2MgO

• NaCl + AgNO₃ → AgCl + NaNO₃

Answer explanation

These reactions demonstrate the fundamental characteristic of oxidation, where oxygen combines with another element to form a new product.