Some Chemical Reactions MCQs with Answers

Which of the following equations represents an addition reaction?

• A.A + B → AB
• B.AB → A + B
• C.AB + CD → AD + CB
• D.CH₄ + 2O₂ → CO₂ + 2H₂O

If 50% of reactants are converted into products, the equilibrium constant (Kc) is?

• A.Less than 1
• B.Greater than 1
• C.Equal to 1
• D.Cannot be determined

The following reaction shows which process: Fuel + Oxygen → Carbon dioxide + Water + Energy?

• A.Respiration
• B.Oxidation
• C.Combustion
• D.Fermentation

Efficiency of chemical reaction can be checked by calculating

• A.Amount of limiting reactant
• B.Percentage yield
• C.Rate of reaction
• D.Activation energy

Ring test is used to confirm the presence of ?

• A.Chloride
• B.Sulphate
• C.Nitrate
• D.Carbonate

Decaying is an example of _?

• A.Physical change
• B.Chemical change
• C.Temporary change
• D.Reversible change

What is the mass of water formed when 4 grams of H₂ and 64 grams of O₂ are combined together?

• A.18 grams
• B.68 grams
• C.36 grams
• D.72 grams

When a strong acid is added to a buffer solution, it results in the formation of ?

• A.Strong acid
• B.Strong base
• C.Weak base
• D.Weak acid

Select the exothermic reaction among the following:

• A.Burning of methane
• B.Photosynthesis
• C.Melting of ice
• D.Evaporation of water

In which redox reaction does only reduction occur?

• A.Fe²⁺ → Fe³⁺
• B.Fe³⁺ → Fe²⁺
• C.Cu → Cu²⁺
• D.Zn → Zn²⁺