- A chemical reaction in which both oxidation and reduction occur simultaneously is called a:
a) Feral reaction
b) Redox reaction
c) Demug reaction
d) Kerol reaction
Answer: b - Nitrogen exhibits oxidation states in the range:
a) –3 to +5
b) –3 to +3
c) –3 to +4
d) –3 to +6
Answer: a - The gain of electrons during a reaction is known as:
a) Oxidation
b) Reduction
c) Radiation
d) Both oxidation and reduction
Answer: b - What causes the rusting of iron?
a) Oxidation and reduction
b) Reduction and oxygen reaction
c) Reaction with CO₂ and oxygen
d) Oxidation and chemical reaction with oxygen
Answer: d - The loss of electrons in a reaction is called:
a) Oxidation
b) Reduction
c) Radiation
d) Oxidation and reduction
Answer: a - What is formed when hydrogen burns in air?
a) Ammonia
b) Water
c) Methane
d) Carbonic acid
Answer: b - The brown coating that forms on iron exposed to air is called:
a) Dust
b) Shovel
c) Spade
d) Rust
Answer: d - The conversion of Fe²⁺ to Fe³⁺ is an example of:
a) Oxidation
b) Reduction
c) Ionisation
d) Nuclear reaction
Answer: a - Which is NOT a feature of an oxidation reaction?
a) Addition of hydrogen
b) Addition of oxygen
c) Loss of electrons
d) Addition of an electronegative element
Answer: a - Rusting of iron is caused by:
a) Oxidation
b) Carbonation
c) Epoxidation
d) Corrosion
Answer: a - Rusting of iron is a:
a) Physical change
b) Electric change
c) Photochemical change
d) None of the above
Answer: d - Coating a thin layer of zinc on steel or iron is known as:
a) Hot dipping
b) Tinning
c) Galvanising
d) Electroplating
Answer: c - Which metal does NOT corrode easily due to its oxide layer?
a) Copper
b) Iron
c) Aluminium
d) Zinc
Answer: c - Applying a protective layer of zinc on water pipes to prevent rusting is called:
a) Zinc coating
b) Alloy formation
c) Vulcanization
d) Galvanization
Answer: d - Which method is NOT suitable to prevent rusting of iron?
a) Annealing
b) Greasing
c) Galvanization
d) Painting
Answer: a - The metal primarily used for galvanising iron is:
a) Zinc
b) Mercury
c) Cadmium
d) Tin
Answer: a - Potassium permanganate is used in water purification because it is a:
a) Reducing agent
b) Oxidising agent
c) Sterilising agent
d) Dissolving agent
Answer: b - Rusting is a:
a) Electrolysis process
b) Oxidation reaction
c) Redox reaction
d) Reduction reaction
Answer: c - Depositing a metal layer on another surface using electricity is called:
a) Electroplating
b) Galvanisation
c) Rusting
d) Crystallisation
Answer: a - During photosynthesis, oxygen is released due to:
a) Hydrolysis of carbohydrates
b) Photolysis of water
c) Reduction of CO₂
d) Breakdown of chlorophyll
Answer: b - In the reaction ZnO + C → Zn + CO, carbon acts as a:
a) Acid
b) Base
c) Reducing agent
d) Oxidising agent
Answer: c - The process of rust formation on iron is known as:
a) Rusting
b) Crystallisation
c) Shoveling
d) Spading
Answer: a - Oxidation involves:
a) Loss of protons
b) Loss of electrons
c) Loss of neutrons
d) Gain of electrons
Answer: b - Browning of pages in old books is due to:
a) Frequent use
b) Lack of air
c) Dust accumulation
d) Oxidation of cellulose
Answer: d - Iron rusts in air when both are present:
a) Carbon dioxide and moisture
b) Water and paint
c) Oxygen and grease
d) Oxygen and moisture
Answer: d - Rusting of iron:
a) Decreases its weight
b) Increases its weight
c) Has no effect on weight
d) Is unpredictable
Answer: b - Iron rusts most rapidly in:
a) Rainwater
b) Distilled water
c) Seawater
d) River water
Answer: c - The metal used for galvanising iron is:
a) Zinc
b) Chromium
c) Lead
d) Antimony
Answer: a - Applying a zinc coat to prevent rusting is called:
a) Galvanization
b) Reduction
c) Corrosion
d) Calcination
Answer: a