Chapter 4, Problem 4.157MP

Interpretation Introduction

(a)

Interpretation:

The number of moles of sulfur present in the given ${\text{MS}}_n$ sample needs to be determined.

Concept introduction:

The number of moles is related to mass and molar mass as follows:

$n=\frac{m}{M}$

Here, m is mass and M is molar mass.

Interpretation Introduction

(b)

Interpretation:

The atomic weight of M needs to be determined.

Concept introduction:

The mass is related to number of moles and molar mass as follows:

$m=n\times M$

Here, n is number of moles and M is molar mass.

Interpretation Introduction

(c)

Interpretation:

The given metal M needs to be identified.

Concept introduction:

The molar mass of any element helps in identifying the element as it is constant for an element. It is mass of the element in its 1 mol. For elements, molar mass is approximately twice its atomic number.

Interpretation Introduction

(d)

Interpretation:

All the chemical equations need to be balanced.

Concept introduction:

An equation for a chemical reaction is said to be balanced, if there are equal number of atoms of same element present on both sides of the reaction arrow.

For any redox reaction, the first step is to determine the two half reactions.

To balance the chemical equation in acid medium, initially atoms other than oxygen and hydrogen are balanced. After that oxygen atoms are balanced by adding ${\text{H}}_{\text{2}}\text{O}$ on the side with lesser number of O atoms. The hydrogen atoms are balanced by adding ${\text{H}}^{+}$ ions. In the last step, charge is balanced by adding electrons.