Chapter 3.5, Problem 3.12PSP

(a)

Interpretation Introduction

Interpretation:

The feasibility of a reaction has to be explained. In the given reaction the oxidizing agent and reducing agent has to be identified.

  ${\text{2Al(s) + 3CuSO}}_{\text{4}}\text{(aq) }\to {\text{ Al}}_{\text{2}}{{\text{(SO}}_{\text{4}}\text{)}}_{\text{3}}\text{(aq) + 3Cu(s) }$

Concept introduction:

Oxidation number:

The oxidation number of an element is zero. The oxidation number of a monoatomic ion equals its charge.

The oxidation number is zero for the summation of the oxidation numbers complete atoms in a complete formula.

The charge on the ion is equal to the summation of the oxidation numbers of complete atoms in poly atomic ion.

The oxidation state of alkali metal $(\text{Li, Na, K, Rb, Cs})$ is $+1$, and alkaline earth metal $\text{(Be, Mg, Ca, Sr, Ba)}$ is  $+2$.

The oxidation state of hydrogen is $+1$ (without bonding with metals), the oxidation state of oxygen is $-2$.

An oxidizing agent gains the electrons and is reduced in a chemical reaction and it is electron acceptor.

A reducing agent loses electrons and is oxidized in a chemical reaction and it is electron donor.

The oxidation state is called as oxidation number, which describes degree of oxidation (loss of electrons) of an atom in a chemical compound. Theoretically, the oxidation state is positive, negative or zero.

Oxidation - reduction reaction: The electrons are transferred to one to other is called oxidation

reduction reaction.

(b)

Interpretation Introduction

Interpretation:

The reaction feasible or not has to be explained. In the given reaction the oxidizing and reducing agent has to be identified.

  ${\text{ 2 Al(s) + Cr}}_{\text{2}}{\text{O}}_{\text{3}}\text{(s) }\to {\text{ Al}}_{\text{2}}{\text{O}}_{\text{3}}\text{(s) + 2 Cr(s) }$

Concept introduction:

Refer to part (a)

(c)

Interpretation Introduction

Interpretation:

The reaction feasible or not has to be explained. In the given reaction the oxidizing and reducing agent has to be identified.

  $\text{ Pt(s) + 4 HCl(aq) }\to {\text{ PtCl}}_{\text{4}}{\text{(aq) + 2 H}}_{\text{2}}\text{(g) }$

Concept introduction:

Refer to part (a)

(d)

Interpretation Introduction

Interpretation:

The reaction feasible or not has to be explained. In the given reaction the oxidizing and reducing agent has to be identified.

  ${\text{ Au(s) + 3AgNO}}_{\text{3}}\text{(aq) }\to {\text{ Au(NO}}_{\text{3}}{\text{)}}_{\text{3}}\text{(aq) + 3Ag(s)}$

Concept introduction:

Refer to part (a)