The number of moles of gas present is 0.0850 mol
Given
initial volume of the gas [tex]v_{i}[/tex]= 0.80 L
final volume of the gas [tex]v_{f}[/tex] = 3.0L
work done by the gas, W = 280 J
constant temperature, T = 300 K
gas constant, R = 8.31 J/mol.K
work done by gas at constant temperature is given as;
[tex]W= \int\limits^a_b {P} \, dv[/tex]
where a =final volume of the gas
and b = initial volume of the gas
W=nRT*ln[tex](\frac{v_{f} }{v_{i} } )[/tex]
[tex]n=\frac{W}{RT*ln\frac{v_{f} }{v_{i} } }[/tex]
[tex]n=\frac{280}{8.31*300*ln\frac{3}{0.80 } }[/tex]
n=0.0850 mol
Therefore, the number of moles of gas present is 0.0850 mol
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