Answer:
2.83 g
Explanation:
At constant temperature and pressure, Using Avogadro's law
[tex]\frac {V_1}{n_1}=\frac {V_2}{n_2}[/tex]
Given ,
V₁ = 2.12 L
V₂ = 3.12 L
n₁ = 0.120 moles
n₂ = ?
Using above equation as:
[tex]\frac{2.12}{0.120}=\frac{3.12}{n_2}[/tex]
[tex]2.12n_2=0.12\cdot \:3.12[/tex]
[tex]2.12n_2=0.3744[/tex]
[tex]n_2=\frac{0.3744}{2.12}[/tex]
[tex]n_2=0.17660[/tex]
n₂ = 0.17660 moles
Molar mass of methane gas = 16.05 g/mol
So, Mass = Moles*Molar mass = 0.17660 * 16.05 g = 2.83 g
2.83 g are in the piston.