Question

Sum of number of protons, electrons, and neutron in 12g of ${}_6^{12}C$ is:

• A. $1.8$
• B. $12.044\times {10}^{23}$
• C. $1.084\times {10}^{25}$
• D. $10.84\times {10}^{24}$

Answer 1

The correct option is C $1.084\times {10}^{25}$

The atomic weight of carbon = 12 g and the given weight = 12 g

As we know that, $\text{No. of moles}=\frac{\text{Given weight}}{\text{Molecular weight}}$

$\therefore$ No. of moles of Carbon in 12 g $=\frac{12}{12}=1\text{mole}$

No. of atoms present in 1 mole of Carbon $=N_A=6.023\times {10}^{23}$

As 1 mole of carbon contains 6 electrons, 6 protons and 6 neutrons.

$\therefore \text{No. of electrons in}6.023\times {10}^{23}\text{atoms of carbon}=6\times 6.023\times {10}^{23}$

Similarly,

$\text{No. of protons in}6.023\times {10}^{23}\text{atoms of carbon}=6\times 6.023\times {10}^{23}$

$\text{No. of neutrons in}6.023\times {10}^{23}\text{atoms of carbon}=6\times 6.023\times {10}^{23}$

$\therefore$ Sum of electrons, protons and neutrons in 12g of carbon = no. of electrons in 12 g carbon + no. of protons in 12 g carbon + no. of neutrons in 12 g carbon

$=6\times 6.023\times {10}^{23}+6\times 6.023\times {10}^{23}+6\times 6.023\times {10}^{23}$

$=108.414\times {10}^{23}=1.084\times {10}^{25}$

So, the correct option is $C$