MCQ Questions on Chemical Reactions

Which of the following is an example of a chemical reaction?

• Melting of ice

• Boiling of water

• Rusting of iron

• Breaking of glass

What type of reaction is represented by the equation: 2H2 + O2 -> 2H2O?

• Decomposition

• Combination

• Displacement

• Redox

Which of the following reactions is an example of a decomposition reaction?

• 2H2O -> 2H2 + O2

• NaCl + AgNO3 -> NaNO3 + AgCl

• Mg + 2HCl -> MgCl2 + H2

• C + O2 -> CO2

What is released in an exothermic reaction?

• Light

• Heat

• Sound

• All of the above

In which type of reaction does one element replace another in a compound?

• Combination

• Decomposition

• Displacement

• Neutralization

Which gas is usually produced when a metal reacts with an acid?

• Oxygen

• Hydrogen

• Carbon dioxide

• Nitrogen

What is the product of the neutralization reaction between hydrochloric acid (HCl) and sodium hydroxide (NaOH)?

• NaCl + H2

• NaCl + H2O

• NaOH + H2O

• NaH + Cl2

What is the common sign of a chemical reaction taking place?

• Change in color

• Formation of gas

• Change in temperature

• All of the above

What happens in a redox reaction?

• Both oxidation and reduction occur

• Only oxidation occurs

• Only reduction occurs

• No electron transfer takes place

Which of the following represents a balanced chemical equation?

• Na + Cl2 -> NaCl

• H2 + O2 -> H2O

• 2H2 + O2 -> 2H2O

• CO2 + H2O -> C6H12O6