Anonymous
Anonymous asked in Science & MathematicsChemistry · 1 month ago

# A 1.82 g sample of an unknown gas is found to occupy a volume of 1.46 L at... The molar mass of the unknown gas is __________ g/mol.?

A 1.82 gram sample of an unknown gas is found to occupy a volume of 1.46 L at a pressure of 772 mmHg and a temperature of 59 °C. Assume ideal behavior.

The molar mass of the unknown gas is __________ g/mol. Relevance

n=PV/RT = 772 mmHg * 1.46 L / 62.36 L∙mmHg/mol∙K * (59+273)K

= 0.054438 mole

molar mass= 1.82 g / 00.054438 = 33.43 g / mol ???

unknown gas indeed

• PV = nRT ... n = PV / RT ... MM (molar mass) = mass / moles = m/n

MM = m/n = m/[PV / RT] = mRT/PV

MM = 1.82*62.4*332 / [772*1.86] = 26.3 g/mole

• n = RT/PV = (62.36)(273.16+59) / (772)(1.46)

molar mass = n/m

where m is mass in grams

you have a calculator....

Ideal gas law

PV = nRT

n = number of moles

R = gas constant = 0.08206 (atm∙L)/(mol∙K)

8.314 L∙kPa/mol∙K

0.08314 L∙bar/mol∙K

62.36 L∙torr/mol∙K

62.36 L∙mmHg/mol∙K

T = temperature in kelvins

P = absolute pressure in atm, kPa, bar, torr

V = volume in liters