Oxidation Reduction MCQs

Oxidation-Reduction (redox) reactions involve the transfer of electrons between chemical species. In simple terms, oxidation is defined as the gain of oxygen atoms, while reduction is the loss of oxygen atoms. Alternatively, a redox reaction can be described as one in which some elements experience a change in their oxidation number. By definition, the oxidizing agent is the substance that contains the atom undergoing a decrease in oxidation number. Essentially, redox reactions are characterized by the transfer of electrons.

A number assigned to each atom or ion in a compound that indicates its degree of oxidation is called

(a) oxidation state only
(b) oxidation number
(c) oxidation degree only
(d) oxidation state and number

The gain of oxygen is known as

(a) oxidation
(b) reduction
(c) halogenation
(d) chlorination

The total of the oxidation number in an element is

(a) charge
(b) volatility
(c) reduction
(d) oxidation

The oxidation number for oxygen will always be

(a) 2
(b) -2
(c) 1
(d) -1

Which of the following is not a reducing agent?

(a) CO2
(b) SO2
(c) NO2
(d) ClO2

Which of the following undergoes a maximum change in its oxidation number when a mixture of oxalic acid, potassium chlorate, and sulfuric acid is heated?

(a) S
(b) Cl
(c) H
(d) C

Reduction is a gain of

(a) electrons
(b) protons
(c) neutrons
(d) oxygen

The reaction in which oxidation and reduction take place at the same time is called

(a) redox reaction
(b) oxidation reaction
(c) reduction reaction
(d) none of the above

Hydrogen (H2) is used for making

(a) margarine only (b) ammonia only (c) salts (d) margarine and ammonia

Reduction is the decrease in

(a) oxidation number
(b) charge
(c) solubility
(d) none of the above