Quiz 4/17

Molecules or Elements on the left side of a chemical reaction are called products.

• True

• False

Answer explanation

In a chemical reaction, molecules or elements on the left side are called reactants, not products. Therefore, the correct choice is False.

Exothermic reactions produce heat and/or light once reacted

• True

• False

Answer explanation

Exothermic reactions release heat and/or light when they occur. In this case, the correct choice is True, as it accurately describes exothermic reactions.

Are combustion reactions exothermic or endothermic?

• Endothermic

• Exothermic

• Both

• Neither

Answer explanation

Combustion reactions are exothermic, releasing heat energy. Therefore, the correct choice is Exothermic.

2H2​+O2​→2H2​O is an example of what kind of reaction?

• Single displacement reaction

• Combination reaction

• Decomposition reaction

• Double displacement reaction

Answer explanation

The reaction 2H2​+O2​→2H2​O is a combination reaction, where two or more substances combine to form a single product.

6 CO₂ + 6 H₂O → C₆H₁₂O₆ + 6 O₂ is an example of what kind of reaction?

• Single displacement reaction

• Combination reaction

• Decomposition reaction

• Double displacement reaction

Answer explanation

The given chemical equation represents a combination reaction, where carbon dioxide and water combine to form glucose and oxygen.

Li₂CO₃ → Li₂O + CO₂ is an example of what kind of reaction?

• Single displacement reaction

• Combination reaction

• Decomposition reaction

• Double displacement reaction

Answer explanation

The given reaction Li2CO3 → Li2O + CO2 is an example of a decomposition reaction, where a compound breaks down into simpler substances.

2 H₂O → 2 H₂ + O₂ is an example of what kind of reaction?

• Single displacement reaction

• Combination reaction

• Decomposition reaction

• Double displacement reaction

Answer explanation

The reaction 2 H2O → 2 H2 + O2 is an example of a decomposition reaction, where a compound breaks down into simpler substances.

Zn + 2 HCl → H₂ + ZnCl₂ is an example of what kind of reaction?

• Single displacement reaction

• Combination reaction

• Decomposition reaction

• Double displacement reaction

Answer explanation

The reaction Zn + 2 HCl → H2 + ZnCl2 is a single displacement reaction, where zinc displaces hydrogen from hydrochloric acid.

A + BC → AC + B is an example of what kind of reaction?

• Single displacement reaction

• Combination reaction

• Decomposition reaction

• Double displacement reaction

Answer explanation

The given reaction A + BC → AC + B is an example of a single displacement reaction, where one element is replaced by another in a compound.

H₂SO₄ + 2 NaOH → Na₂SO₄ + 2 H₂O is an example of what kind of reaction?

• Single displacement reaction

• Combination reaction

• Decomposition reaction

• Double displacement reaction

Answer explanation

The reaction H2SO4 + 2 NaOH → Na2SO4 + 2 H2O is a double displacement reaction, where the ions of two compounds exchange places to form new compounds.