Chapter 5, Problem 54AE

(a)

Interpretation Introduction

Interpretation:

The percent of electrons to the total mass of one aluminium atom has to be given.

Answer to Problem 54AE

The percent of electrons in an aluminium atom is $\text{0}\text{.2642\%}\text{.}$

Explanation of Solution

Given,

The mass of one aluminum atom is $\text{4}{\text{.480×10}}^{\text{-23}}\text{g}\text{.}$

The mass of an electron is $\text{9}{\text{.1093897×10}}^{\text{-27}}\text{g}\text{.}$

The total number of electrons in $\text{Al}$ is $13.$

The mass percent can be calculated as,

  $\text{Mass}\text{percent=}\frac{\text{Mass}\text{of}\text{electron}}{\text{Mass}\text{of}\text{atom}}\text{×100}$

  $\text{Mass}\text{percent=}\frac{\text{13×9}{\text{.1093877×10}}^{\text{-27}}\text{g}}{\text{4}{\text{.480×10}}^{\text{-23}}\text{g}}\text{×100}$

  $\text{Mass}\text{percent=0}\text{.2642\%}$

The percent of electrons in an aluminium atom is $\text{0}\text{.2642\%}\text{.}$

(b)

Interpretation Introduction

Interpretation:

The percent of electrons to the total mass of one phosphorus atom has to be given.

Answer to Problem 54AE

The percent of electrons in phosphorus atom is $\text{0}\text{.2656\%}\text{.}$

Explanation of Solution

Given,

The mass of one phosphorus atom is $\text{5}{\text{.143×10}}^{\text{-23}}\text{g}\text{.}$

The mass of an electron is $\text{9}{\text{.1093897×10}}^{\text{-27}}\text{g}\text{.}$

The total number of electrons in $\text{P}$ is $15.$

The mass percent can be calculated as,

  $\text{Mass}\text{percent=}\frac{\text{Mass}\text{of}\text{electron}}{\text{Mass}\text{of}\text{atom}}\text{×100}$

  $\text{Mass}\text{percent=}\frac{\text{15×9}{\text{.1093877×10}}^{\text{-27}}\text{g}}{\text{5}{\text{.143×10}}^{\text{-23}}\text{g}}\text{×100}$

  $\text{Mass}\text{percent=0}\text{.2656\%}$

The percent of electrons in phosphorus atom is $\text{0}\text{.2656\%}\text{.}$

(c)

Interpretation Introduction

Interpretation:

The percent of electrons to the total mass of one Krypton atom has to be given.

Answer to Problem 54AE

The percent of electrons in Krypton atom is $\text{0}\text{.2355\%}\text{.}$

Explanation of Solution

Given,

The mass of one Krypton atom is $\text{1}{\text{.392×10}}^{\text{-22}}\text{g}\text{.}$

The mass of an electron is $\text{9}{\text{.1093897×10}}^{\text{-27}}\text{g}\text{.}$

The total number of electrons in $\text{Kr}$ is $36.$

The mass percent can be calculated as,

  $\text{Mass}\text{percent=}\frac{\text{Mass}\text{of}\text{electron}}{\text{Mass}\text{of}\text{atom}}\text{×100}$

  $\text{Mass}\text{percent=}\frac{\text{36×9}{\text{.1093877×10}}^{\text{-27}}\text{g}}{\text{1}{\text{.392×10}}^{\text{-22}}\text{g}}\text{×100}$

  $\text{Mass}\text{percent=0}\text{.2355\%}$

The percent of electrons in Krypton atom is $\text{0}\text{.2355\%}\text{.}$

(d)

Interpretation Introduction

Interpretation:

The percent of electrons to the total mass of one platinum atom has to be given.

Answer to Problem 54AE

The percent of electrons in platinum atom is $\text{0}\text{.2193\%}\text{.}$

Explanation of Solution

Given,

The mass of one platinum atom is $\text{3}{\text{.240×10}}^{\text{-22}}\text{g}\text{.}$

The mass of an electron is $\text{9}{\text{.1093897×10}}^{\text{-27}}\text{g}\text{.}$

The total number of electrons in $\text{Pt}$ is $78.$

The mass percent can be calculated as,

  $\text{Mass}\text{percent=}\frac{\text{Mass}\text{of}\text{electron}}{\text{Mass}\text{of}\text{atom}}\text{×100}$

  $\text{Mass}\text{percent=}\frac{\text{78×9}{\text{.1093877×10}}^{\text{-27}}\text{g}}{\text{3}{\text{.240×10}}^{\text{-22}}\text{g}}\text{×100}$

  $\text{Mass}\text{percent=0}\text{.2193\%}$

The percent of electrons in platinum atom is $\text{0}\text{.2193\%}\text{.}$