Chapter 4, Problem 96A

Interpretation Introduction

Interpretation:

Composition of various isotopes is to be calculated from the given table.

Concept introduction:

Isotope of any elements contains same number of protons but different number of neutrons. And with the help of given number of protons and neutrons the atomic number and atomic mass can be calculated.

Answer to Problem 96A

Composition of various isotopes
Isotope	S-32	Ca-44	Zn-64	F-19	Na-23
Atomic number	16	20	30	9	11
Mass number	32	44	64	19	23
Number of protons	16	20	30	9	11
Number of neutrons	16	24	34	10	12
Number of electron	16	20	30	9	11

Explanation of Solution

Given information:

Table 8 composition of various isotopes
Isotope			Zn-64
Atomic number				9	11
Mass number	32				23
Number of protons	16
Number of neutrons		24		10
Number of electron		20

From the given table −

• The mass number is 32 and the number of protons is 16.

Now:

$\text{The number of protons =Atomic number}\text{.}$

$\text{The number of protons=16}$

$\text{The atomic number of isotope=16}$

Now:

$\text{The number of protons =Number of electron}$

$\text{The given number of protons =16}$

$\text{The number of electrons=16}$

$\text{Mass number=number of protons +Number of neutrons}$

$\text{The given number of protons =16 and the Mass number=32 }$

$\text{Number of neutron=Mass number-Number of protons}$

$\text{Number}\text{of}\text{neutrons=}\text{32-16}$

$\text{Number}\text{of}\text{neutrons=16}$

• The number of neutrons is 24 and the number of electron is 20.

$\text{The number of electrons=Number of protons}$

Therefore, $\text{The number of protons= 20}$

$\text{The atomic number= Number of protons=20}$

$\text{Mass number=Number of protons- Number of neutrons}$

$\text{Mass number= 20+24}$

$=44$

• The atomic mass is 64 and the atomic number is 30.

$\begin{array}{l}\text{The atomic number=Number of protons}\hfill \\ \text{The given atomic number=30 }\hfill \\ \text{The number of protons=30}\hfill \\ \text{The number of protons=Number of electrons}\text{.}\hfill \\ \text{So,}\hfill \\ \text{The number of electron=30}\text{.}\hfill \\ \text{The given atomic mass is 64}\text{.}\hfill \\ \text{Mass number=Number of protons + Number of neutrons}\text{.}\hfill \\ \text{So,}\hfill \\ \text{The number of neutrons= Mass number –Number of protons}\text{.}\hfill \\ \text{ =64-30}\hfill \\ \text{ =34}\hfill \end{array}$

• The given atomic number is 9 and the number of neutrons is 10.

$\begin{array}{l}\text{The atomic number = Number of protons}\hfill \\ \text{The given atomic number=9}\hfill \\ \text{So,}\hfill \\ \text{The number of protons=9}\hfill \\ \text{Mass number = Number of protons + Number of neutrons}\hfill \\ \text{ =9+10}\hfill \\ \text{ = 19}\hfill \\ \text{Number of protons=Number of electrons}\hfill \\ \text{The number of protons=9}\hfill \\ \text{So,}\hfill \\ \text{Number of electron=9}\hfill \end{array}$

• The given atomic number 11 and the mass number 23.

$\begin{array}{l}\text{The atomic number= Number of protons}\text{.}\hfill \\ \text{So,}\hfill \\ \text{The number of protons=11}\text{.}\hfill \\ \text{The number of protons=Number of electron}\text{.}\hfill \\ \text{The number of electron=11}\hfill \\ \text{Mass number = Number or protons + Number of neutrons}\hfill \\ \text{So,}\hfill \\ \text{The number of neutrons = Mass number – number of protons}\hfill \\ \text{ =23-11 =12}\text{.}\hfill \end{array}$

Conclusion

The different isotopes composition is calculated by the given information about the number of electrons and the number of neutrons, protons as well as the atomic number and atomic mass.