Some Chemical Reactions MCQs with Answers

Past Paper MCQ

Water and salt is produced by reaction of acid with

• A.Base
• B.Metal oxide
• C.Non-metal
• D.Carbon dioxide

Carboxylic acid reacts with metal carbonate. The colorless gas evolved is?

• A.Hydrogen
• B.Carbon dioxide
• C.Oxygen
• D.Nitrogen

What type of energy results from chemical reactions between atoms or molecules?

• A.Electrical energy
• B.Nuclear energy
• C.Thermal energy
• D.Chemical energy

The substance which reduces other substances and itself gets oxidized during this process is called ?

• A.Oxidizing agent
• B.Catalyst
• C.Reducing agent
• D.Electrolyte

What are the products in the reaction: CH4 + 2O2 → CO2 + 2H2O?

• A.Carbon dioxide and Water
• B.Carbon monoxide and Hydrogen
• C.Methane and Oxygen
• D.Carbon and Hydrogen peroxide

Which step is irrelevant with respect to balancing of redox equations by oxidation number method?

• A.Assign oxidation numbers to all atoms
• B.Equalize the total increase and decrease in oxidation numbers
• C.Calculate the increase and decrease in oxidation numbers
• D.Split the reaction into two half reactions

Ethyne can be prepared using 1,2-dibromoethane as starting material. What else is used in its preparation?

• A.Alcoholic KOH
• B.Aqueous KOH
• C.Dilute H₂SO₄
• D.Alcoholic NaOH

The reaction between two HF and SbF₅ leads to the formulation of ?

• A.[SbF₄]⁺ + HF₂⁻
• B.[SbF₅]⁻ + 2HF
• C.[SbF₆]⁻ + 2H⁺ + F⁻
• D.[SbF₆]⁻ + H₂F⁺

Reaction of HCN with formaldehyde is a ?

• A.Nucleophilic addition reaction
• B.Electrophilic addition reaction
• C.Nucleophilic substitution reaction
• D.Free radical addition reaction

SN₂ reaction can be best carried out with _?

• A.Primary alkyl halide
• B.Secondary alkyl halide
• C.Tertiary alkyl halide
• D.None of these