Chapter 4, Problem 67A

Carbon A carbon atom has a mass number of 12 and an atomic number of 6. How many neutrons does it have?

Interpretation Introduction

Interpretation:

Number of neutrons in carbon atom with mass number of 12 and atomic number of 6 is to be calculated.

Concept introduction:

Mass number is the total number of protons and neutrons present in the nucleus of an atom.

Answer to Problem 67A

$\text{Number of neutrons = 6}$

Explanation of Solution

Atomic number of an atom is also referred as number of protons

Therefore,

$\begin{array}{l}\text{Atomic number = Number of protons}\hfill \\ \text{Number of protons = 6}\hfill \end{array}$

Mass number is the total number of protons and neutrons present in the nucleus of an atom.

$\begin{array}{l}\text{Mass number = Number of proton + Number of neutrons}\hfill \\ \text{Number of neutrons = Mass number – Number of proton}\hfill \\ \text{ = 12 – 6}\hfill \\ \text{ = 6}\hfill \end{array}$

Conclusion

Number of neutrons found in carbon atom with mass number of 12 and atomic number 6 is 6.