Some Chemical Reactions MCQs with Answers

How many grams of CO2 can be produced by thermally decomposing 10 moles of ZnCO3(S)?

• A.220 g
• B.440 g
• C.880 g
• D.44 g

Sod-benzoate on reacting with soda lime forms?

• A.Benzene
• B.Benzoic acid
• C.Phenol
• D.Toluene

Consider the following equation: 4Fe + 3O₂ → 2Fe₂O₃. The combined mass of the reactants is, for example, 320 grams. The mass of the product will be _?

• A.320 grams
• B.160 grams
• C.640 grams
• D.480 grams

What happens in the rusting of iron?

• A.Reduction
• B.Oxidation
• C.Neutralization
• D.Dehydration

The storage battery provides electrical energy through ?

• A.Chemical reactions
• B.Mechanical motion
• C.Nuclear fission
• D.Thermal conduction

Which of the following is a chemical reaction?

• A.Melting of ice
• B.Rusting of iron
• C.Boiling of water
• D.Cutting of wood

Which gas is produced when trees and fossil fuels are burnt?

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

Which reagent gives a colorless homogeneous solution when added to phenol?

• A.Aqueous sodium hydroxide
• B.Aqueous sodium bicarbonate
• C.Aqueous hydrochloric acid
• D.Bromine water

When vegetable oils or animal fats are treated with sodium hydroxide, soap is formed along with glycerin. Glycerin during the soap separation process _?

• A.Crystallizes and is filtered out
• B.Floats on top as a separate layer
• C.Evaporates due to the heat of the reaction
• D.Dissolves in the sodium chloride solution and settles at the bottom

Formation of water molecule from gaseous hydrogen and oxygen proceeds through _?

• A.Addition reaction
• B.Substitution reaction
• C.Decomposition reaction
• D.Neutralization reaction