Step 1
The He gas is assumed to be ideal. Therefore, the next equation is applied:
[tex]p\text{ x V = n x R x T \lparen1\rparen}[/tex]----------------------
Step 2
Information provided:
p = pressure = 1.13 atm
V = volume = 33.2 L
n = number of moles = unknown
T = absolute temperature = 652 K
R = gas constant = 0.082 atm L/mol K
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Step 3
Firstly, n is calculated from (1):
[tex]\begin{gathered} \frac{p\text{ x V}}{R\text{ x T}}=\text{ n} \\ \frac{1.13\text{ atm x 33.2 L}}{0.082\text{ }\frac{atm\text{ L}}{mol\text{ K}}x652\text{ K}}=0.702\text{ moles} \end{gathered}[/tex]n = 0.702 moles
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Step 4
The mass of He is calculated as:
n = mass/the molar mass He
The molar mass of He = 4.00 g
So, n = mass/4.00 g/mol
n x 4.00 g/mol = mass
0.702 moles x 4.00 g/mol = 2.81 g
Answer: mass = 2.81 g