Redox Reactions

Q. $2CuI\to Cu+Cu{I}_2$, the reaction is

1. Redox
2. Neutalisation
3. Oxidation
4. Reduction

Q. Oxidants are substances that show:

1. Decrease in oxidation number
2. Oxidize others and reduce themselves
3. All the above
4. Gain electrons during a change

Q. Reduction involves

1. Loss of e^–
2. gain of
3. Increase in valency of positive part
4. Decrease in valency of negative part

Q. Which of the following statements is incorrect:

1. Hydrogen preoxide can be used as a bleaching agent as it is a good oxidant
2. Hydrogen peroxide can restore the color of old paintings
3. Hydrogen peroxide contains peroxide linkage in it's structure
4. None of the above

Q. Oxidation is a process that involves:

1. De-electronation
2. Addition of hydrogen
3. Addition of metal
4. De-protonation

Q. When $H_{2}S$ reacts with a halogen, the halogen

1. are reducted
2. from sulphur halides
3. None of these
4. Mg is oxidized

Q. In a redox reaction, oxidation number of a reductant:

1. increases
2. decreases
3. does not change
4. cannot be predicted

Q. $H_{2}S$ is ______ to S:

1. None of these
2. Oxidized
3. Reduced
4. Precipitated

Q. The conversion of $Pb{O}_{2}toPb(N{O}_3{)}_2$ is

1. Reduction
2. Oxidation
3. Neither Oxidation nor reduction
4. Both oxidation & reduction

Q. In a redox reaction, oxidation number of an oxidant:

1. increases
2. decreases
3. does not change
4. cannot be predicted