Some Chemical Reactions MCQs with Answers

The enthalpy change when 1 mole of water is formed by the reaction of an acid with an alkali under standard conditions is known as?

• A.Enthalpy of solution
• B.Enthalpy of combustion
• C.Enthalpy of formation
• D.Enthalpy of neutralization

Chemical changes are those changes in which?

• A.Only physical state changes
• B.New substance is formed
• C.No energy is absorbed or released
• D.Original substance can be easily recovered

How do we use the chemical energy in fuels like coal?

• A.By exposing them to sunlight
• B.By freezing them
• C.By dissolving them in water
• D.By burning them

Which gas is emitted by incomplete combustion of fuel?

• A.Carbon Dioxide
• B.Carbon Monoxide
• C.Nitrogen Dioxide
• D.Sulfur Dioxide

All of the following are true statements concerning a catalyst except?

• A.A catalyst remains unchanged chemically at the end of the reaction
• B.A catalyst lowers the activation energy of a reaction
• C.A catalyst will be used up in a reaction
• D.A small amount of catalyst is sufficient to catalyze a reaction

Chlorine upon reaction with NaOH in cold yields ?

• A.NaCl, NaClO₃, H₂O
• B.NaCl, NaClO, H₂O
• C.NaCl, NaClO₂, H₂O
• D.NaClO₃, NaClO, H₂O

Which of the following equations represents a decomposition reaction?

• A.A + B → AB
• B.AB → A + B
• C.AB + CD → AD + CB
• D.A + BC → AC + B

Acid and carbonates react together to produce _?

• A.Salt and water
• B.Salt, carbon dioxide, and water
• C.Salt and hydrogen gas
• D.All of these

Which of the following phenomena occur when a small amount of acid is added to water?

• A.Dilution and Ionisation
• B.Precipitation and Neutralisation
• C.Oxidation and Reduction
• D.Condensation and Evaporation

Zero order reaction are those reactions

• A.In which rate of reaction is independent of concentration of reactants
• B.In which rate of reaction is directly proportional to concentration of reactants
• C.In which rate of reaction is equal to rate constant
• D.In which rate of reaction is inversely proportional to concentration of reactants