A balloon contains 0.62 moles of helium at 481 mm Hg and 13 °C. The volume of the ballon is ____ liters.

Answer 1

Use the Ideal Gas Law: PV = nRT

P = pressure in atmospheres = 481 mm Hg x 1 atm/760 mm Hg = 0.633 atm

V = volume in liters = ?

n = moles = 0.62 moles

R = gas constant = 0.0821 Latm/Kmol

T = temperature in Kelvin = 13ºC + 273 = 286K

Substituting our values and solving for V, we have ...

V = nRT / P

V = (0.62)(0.0821)(286) / (0.633)

V = 23 liters (2 sig. figs.)