chemistry hw help

Question

Calculate the density of a NH3 gas having a pressure of 34mmHg and a temperature of 233K

Answer 1

Assume a volume of 1 liter

PV = nRT

P = pressure = 34 mm Hg x 1 atm/760 atm = 0.0447 atm

V = volume = 1 L

n = moles = ?

R = gas constant = 0.0821 Latm/Kmol

T = temp in K = 233K

Solve for n (moles):

n = PV/RT = (0.0447)(1) / (0.0821)(233)

n = 0.002339 moles NH3

molar mass NH3 = 17 g /mol

mass NH3 = 0.002339 moles x 17 g/mol = 0.0398 g NH3

Density = mass/volume = 0.0398 g / L