Question

What will be the correct no. of total electrons in $1.6\, g$ methane

• A. $6.02 \times 10^{24}$
• B. $6.02 \times 10^{23}$
• C. $6.02 \times 10^{22}$
• D. $9.632 \times 10^{23}$

Answer 1

Answer: (B)

Given, mass $=1.6\, g$ of methane

Therefore, moles of methane $=\frac{\text { given mass }}{\text { molecular mass }}$

$=\frac{1.6\, g }{16\, g\, mol ^{-1}}=0.1\, mol$

1 mole of methane has $6.022 \times 10^{23}$ molecules.

$\therefore 0.1$ mole of methane has

$6.022 \times 10^{23} \times 0.1 \text { molecules }$

$= 6.022 \times 10^{22} \text { molecules }$

Now, 1 mole of methane has 10 electrons

$\therefore 0.1$ mole of methane has

$=10 \times 6.022 \times 10^{22}$ electrons

$=6.022 \times 10^{23}$ electrons