Chapter 7.4, Problem 40PP

(a)

Interpretation Introduction

Interpretation:To calculate the mass percent composition in CaCl₂.

Concept Introduction :

Mass percent composition can be easily calculated by using the below formula:

Let’s say we have a molecule A₃B₂. Then,

  $\begin{array}{l}\text{Mass \% composition of atom A =}\frac{\text{no}\text{.}\text{of}\text{mole}\text{of}\text{A}\text{atom}\text{in}\text{molecule}\text{×atomic}\text{mass}\text{of}\text{A}\text{atom}}{\text{molar}\text{mass}\text{of}{\text{A}}_{\text{3}}{\text{B}}_{\text{2}}}\text{×100}\\ \text{Mass \% composition of atom B =}\frac{\text{no}\text{.}\text{of}\text{mole}\text{of}\text{B}\text{atom}\text{in}\text{molecule}\text{×}\text{atomic}\text{mass}\text{of}\text{B}\text{atom}}{\text{molar}\text{mass}\text{of}{\text{A}}_{\text{3}}{\text{B}}_{\text{2}}}\text{×100}\end{array}$

(b)

Interpretation Introduction

Interpretation:To calculate the mass percent composition in Na₂Cr₂O₇.

Concept Introduction :

Mass percent composition can be easily calculated by using the below formula:

Let’s say we have a molecule A₃B₂. Then,

  $\begin{array}{l}\text{Mass \% composition of atom A =}\frac{\text{no}\text{.}\text{of}\text{mole}\text{of}\text{A}\text{atom}\text{in}\text{molecule}\text{×atomic}\text{mass}\text{of}\text{A}\text{atom}}{\text{molar}\text{mass}\text{of}{\text{A}}_{\text{3}}{\text{B}}_{\text{2}}}\text{×100}\\ \text{Mass \% composition of atom B =}\frac{\text{no}\text{.}\text{of}\text{mole}\text{of}\text{B}\text{atom}\text{in}\text{molecule}\text{×}\text{atomic}\text{mass}\text{of}\text{B}\text{atom}}{\text{molar}\text{mass}\text{of}{\text{A}}_{\text{3}}{\text{B}}_{\text{2}}}\text{×100}\end{array}$

(c)

Interpretation Introduction

Interpretation:To calculate the mass percent composition in C₂H₃Cl₃.

Concept Introduction :

Mass percent composition can be easily calculated by using the below formula:

Let’s say we have a molecule A₃B₂. Then,

  $\begin{array}{l}\text{Mass \% composition of atom A =}\frac{\text{no}\text{.}\text{of}\text{mole}\text{of}\text{A}\text{atom}\text{in}\text{molecule}\text{×atomic}\text{mass}\text{of}\text{A}\text{atom}}{\text{molar}\text{mass}\text{of}{\text{A}}_{\text{3}}{\text{B}}_{\text{2}}}\text{×100}\\ \text{Mass \% composition of atom B =}\frac{\text{no}\text{.}\text{of}\text{mole}\text{of}\text{B}\text{atom}\text{in}\text{molecule}\text{×}\text{atomic}\text{mass}\text{of}\text{B}\text{atom}}{\text{molar}\text{mass}\text{of}{\text{A}}_{\text{3}}{\text{B}}_{\text{2}}}\text{×100}\end{array}$

(d)

Interpretation Introduction

Interpretation:To calculate the mass percent composition in Ca₃(PO₄)₂.

Concept Introduction :

Mass percent composition can be easily calculated by using the below formula:

Let’s say we have a molecule A₃B₂. Then,

  $\begin{array}{l}\text{Mass \% composition of atom A =}\frac{\text{no}\text{.}\text{of}\text{mole}\text{of}\text{A}\text{atom}\text{in}\text{molecule}\text{×atomic}\text{mass}\text{of}\text{A}\text{atom}}{\text{molar}\text{mass}\text{of}{\text{A}}_{\text{3}}{\text{B}}_{\text{2}}}\text{×100}\\ \text{Mass \% composition of atom B =}\frac{\text{no}\text{.}\text{of}\text{mole}\text{of}\text{B}\text{atom}\text{in}\text{molecule}\text{×}\text{atomic}\text{mass}\text{of}\text{B}\text{atom}}{\text{molar}\text{mass}\text{of}{\text{A}}_{\text{3}}{\text{B}}_{\text{2}}}\text{×100}\end{array}$

(e)

Interpretation Introduction

Interpretation:To calculate the mass percent composition in C₁₈H₃₆O₂.

Concept Introduction :

Mass percent composition can be easily calculated by using the below formula:

Let’s say we have a molecule A₃B₂. Then,

  $\begin{array}{l}\text{Mass \% composition of atom A =}\frac{\text{no}\text{.}\text{of}\text{mole}\text{of}\text{A}\text{atom}\text{in}\text{molecule}\text{×atomic}\text{mass}\text{of}\text{A}\text{atom}}{\text{molar}\text{mass}\text{of}{\text{A}}_{\text{3}}{\text{B}}_{\text{2}}}\text{×100}\\ \text{Mass \% composition of atom B =}\frac{\text{no}\text{.}\text{of}\text{mole}\text{of}\text{B}\text{atom}\text{in}\text{molecule}\text{×}\text{atomic}\text{mass}\text{of}\text{B}\text{atom}}{\text{molar}\text{mass}\text{of}{\text{A}}_{\text{3}}{\text{B}}_{\text{2}}}\text{×100}\end{array}$