The number of atoms in $0.1\text{mol}$triatomic gas is:

The correct option is A

$1.806\times {10}^{23}$

Explanation:

Calculating the number of atoms:

Given, mole of triatomic gas = 0.1

The number of molecules of triatomic can be calculated using the given formula

$\text{Number of molecules=moles×Avogadro number}$

Since one triatomic gas molecule contains three atoms. So, the total number of atoms can be calculated as

$$\begin{gathered} \text{Number of atoms=3×Number of mole×Avogadro number} \\ =3\times 0.1{\text{mol×6.022×10}}^{23}{\text{mol}}^{\text{-1}} \\ =1.806{\times 10}^{23} \end{gathered}$$

Hence, the number of atoms is $1.806\times {10}^{23}$.

Hence, option (A) is correct.