Answer:
[tex]\large \boxed{\text{7.94 g/mol}}[/tex]
Explanation:
We can use the Ideal Gas Law to solve this problem
pV = nRT
Data:
p = 0.998 atm
V = 0.153 L
T = 26 °C
m = 0.0494 g
1. Convert temperature to kelvins
T = (26 + 273.15) K = 299.15 K
2. Calculate the number of moles
[tex]\text{0.998 atm} \times\text{0.153 L} = n \times \text{0.082 06 L}\cdot\text{atm}\cdot\text{K}^{-1}\text{mol}^{-1}\times \text{299.15 K}\\\\0.1527 = n \times \text{24.55 mol}^{-1}\\\\n = \dfrac{0.1527}{\text{24.55 mol}^{-1}} = 6.220 \times 10^{-3} \text{ mol}[/tex]
3. Calculate the molar mass
[tex]\text{Molar mass} = \dfrac{\text{mass}}{\text{moles}}\\\\M = \dfrac{m}{n}\\\\M = \dfrac{\text{0.0494 g}}{6.220 \times 10^{-3} \text{ mol}}\\\\M = \textbf{7.94 g/mol}\\\text{The molar mass of the gas is } \large \boxed{\textbf{7.94 g/mol}}[/tex]
