Chapter 13, Problem 13.149MP

Interpretation Introduction

(a)

Interpretation:

The number of moles of hydrogen gas evolved needs to be determined when 1.385 g of an unknown metal is reacted with an excess of HCl to evolve the gas with a volume of 382.6 mL at 20.0°C and 755 mmHg pressure.

Concept introduction:

Solution stoichiometry involves the calculation of the concentration of solutions in the given conditions of volumes, moles, etc. There are various ways to calculate the concentration of solutions such as molarity, molality, mole fraction, ppm, ppb etc. Mole fraction is the ratio of moles of substance and total moles in the solution or mixture. One ppm stands for part per million or milligrams per liter (mg/L) whereas parts per billion (ppb) is one part in 1 billion.

Molarity represents the moles of solute dissolved in per liter of solution. The mathematical expression of molarity is:

$\text{Molarity=}\frac{\text{Moles of solute}}{\text{Volume of solution (L)}}$

Interpretation Introduction

(b)

Interpretation:

The mass of ${\text{MCl}}_{\text{x}}$ formed needs to be determined.

Concept introduction:

From the number of moles and molar mass, the mass of substance can be calculated as follows:

$m=n\times M$

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

Interpretation Introduction

(c)

Interpretation:

The molality of particles of ${\text{MCl}}_{\text{x}}$ formed needs to be determined.

Concept introduction:

Molality represents the moles of solute dissolve in per kg of solvent. The mathematical expression of molality is:

$\text{Molality=}\frac{\text{Moles of solute}}{\text{Mass of solvent (kg)}}$

From freezing point depression, the molality can be determined using the following relation:

$\Delta {\text{T}}_{\text{f}}\text{ = i}\times {\text{ K}}_{\text{f}}\times \text{ molality}$

Interpretation Introduction

(d)

Interpretation:

The number of moles of ions present in solution of ${\text{MCl}}_{\text{x}}$ needs to be determined.

Concept introduction:

Solution stoichiometry involves the calculation of the concentration of solutions in the given conditions of volumes, moles, etc. There are various ways to calculate the concentration of solutions such as molarity, molality, mole fraction, ppm, ppb etc. Mole fraction is the ratio of moles of substance and total moles in the solution or mixture. One ppm stands for part per million or milligrams per liter (mg/L) whereas parts per billion (ppb) is one part in 1 billion.

Molarity represents the moles of solute dissolved in per liter of solution. The mathematical expression of molarity is:

$\text{Molarity=}\frac{\text{Moles of solute}}{\text{Volume of solution (L)}}$

Interpretation Introduction

(e)

Interpretation:

The formula and molecular weight of ${\text{MCl}}_{\text{x}}$ formed needs to be determined.

Concept introduction:

Solution stoichiometry involves the calculation of the concentration of solutions in the given conditions of volumes, moles, etc. There are various ways to calculate the concentration of solutions such as molarity, molality, mole fraction, ppm, ppb etc. Mole fraction is the ratio of moles of substance and total moles in the solution or mixture. One ppm stands for part per million or milligrams per liter (mg/L) whereas parts per billion (ppb) is one part in 1 billion.

Molarity represents the moles of solute dissolved in per liter of solution. The mathematical expression of molarity is:

$\text{Molarity=}\frac{\text{Moles of solute}}{\text{Volume of solution (L)}}$

Interpretation Introduction

(f)

Interpretation:

The metal M in ${\text{MCl}}_{\text{x}}$ needs to be identified.

Concept introduction:

Solution stoichiometry involves the calculation of the concentration of solutions in the given conditions of volumes, moles, etc. There are various ways to calculate the concentration of solutions such as molarity, molality, mole fraction, ppm, ppb etc. Mole fraction is the ratio of moles of substance and total moles in the solution or mixture. One ppm stands for part per million or milligrams per liter (mg/L) whereas parts per billion (ppb) is one part in 1 billion.

Molarity represents the moles of solute dissolved in per liter of solution. The mathematical expression of molarity is:

$\text{Molarity=}\frac{\text{Moles of solute}}{\text{Volume of solution (L)}}$