Question

The total number of atoms present in 176 g of $C{O}_2$ is

• A.
  $16N_A$
• B.
  $24N_A$
• C.
  $12N_A$
• D.
  $22N_A$

Answer 1

The correct option is C

$12N_A$
Molar mass of $C{O}_2=44gmo{l}^{–1}\text{Number of moles of}C{O}_2=\frac{\text{Given mass}}{\text{Molar Mass}}=\frac{176}{44}=4$

Number of atoms in 1 molecule of $C{O}_2=3$

Number of molecules in 1 mole of $C{O}_2=N_A$

$\therefore$ Number of molecules in 4 moles of $C{O}_2=4N_A$

$\Rightarrow$ Number of atoms in 4 moles of $C{O}_2=4N_A\times 3=12N_A$

Hence, the correct answer is option (c).