Chemical Reactions & Equations MCQ

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

• Acid-base reaction

• Single displacement reaction

• Combination reaction

• Decomposition reaction

What type of reaction is represented by the following equation: 2Mg + O2 -> 2MgO?

• Combination reaction

• Decomposition reaction

• Acid-base reaction

• Single displacement reaction

In a double displacement reaction, what happens?

• Atoms combine to form new molecules

• Positive ions and negative ions of two ionic compounds switch places

• The reaction does not result in any products

• Only one reactant is involved

What is the product of a combustion reaction involving hydrocarbons?

• Nitrogen and sulfur dioxide

• Methane and oxygen

• Carbon monoxide and nitrogen oxides

• Carbon dioxide and water

What type of reaction is represented by the following equation: Fe + S -> FeS?

• Single displacement reaction

• Synthesis reaction

• Decomposition reaction

• Combustion reaction

What happens in a decomposition reaction?

• No substances are formed

• A compound remains unchanged

• A single compound breaks down into two or more simpler substances.

• A single compound combines with another compound

What type of reaction is represented by the following equation: 2NaCl -> 2Na + Cl2?

• Synthesis reaction

• Single displacement reaction

• Combustion reaction

• Decomposition reaction

What is the general formula for a synthesis reaction?

• AB -> A + B

• A -> AB + B

• A + B -> AB

• A + B -> BA

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

• Single displacement reaction

• Synthesis reaction

• Combustion reaction

• Decomposition reaction

What is the key characteristic of a single displacement reaction?

• One element replaces another element in a compound

• Two elements replace each other in a compound

• No elements are replaced in a compound

• The compound remains unchanged