The number of peroxide linkages in CrO₅ is /are :

1. One

2. Two

3. Three

4. None of the above

Conversion of PbSO₄ to PbS is:

1. Reduction of S

2. Oxidation of S

3. Dissociation

4. None of the above

Which of the following reactions represents the reduction of hydrogen?

1. Carbon Monoxide + Copper Oxide $\to$ Carbon Dioxide + Copper

2. Copper Oxide + Hydrochlorid Acid $\to$ Water + Copper Chloride

3. Steam + Iron $\to$Hydrogen + Iron oxide

4. Hydrogen+ Iron Oxide $\to$ Water + Iron

The oxidation number of Fe in K₃[Fe(CN)₆] is:

1. +2

2. +3

3. +4

4. +1

It is found that v forms a double salt isomorphous with Mohr's salt. The oxidation number of V in this compound is:

1. +3

2. +2

3. +4

4. -4