Answer to Question #252029 in General Chemistry for Paul

Question

A 1.25-g sample of CO2 is contained in a 750.-mL flask at 22.5 °C. What is the pressure

of the gas?

Answer 1

$m=1.25 \;g \\ V=750 \;mL = 0.75 \;L \\ T= 22.5+273.15 = 295.65 \;K \\ M(CO_2) = 44.01 \;g/mol \\ n(CO_2) = \frac{1.25}{44.01} = 0.0284 \;mol$

Ideal gas law

pV = nRT

R = 0.08206 L×atm/mol×K

$p=\frac{nRT}{V} \\ p= \frac{0.0284 \times 0.08206 \times 295.65}{0.75} = 0.918 \;atm$

Answer: 0.918 atm