Answer:
Molar mass of gas = 160 g/mol
Explanation:
Given data:
Mass of sample gas = 1.28 g
Temperature of sample gas = 127°C (127+273 = 400K)
Pressure of sample gas = 1 atm
Volume of sample gas = 0.250 L
Molar mass of gas = ?
Solution:
Formula:
PV = nRT
R = general gas constant = 0.0821 atm.L/ mol.K
Now we will put the values in formula.
1 atm × 0.250 L = n × 0.0821 atm.L/ mol.K ×400K
0.250 L.atm = n ×32.84atm.L/ mol
n = 0.250 L.atm/32.84atm.L/ mol
n = 0.008 mol
Molar mass of gas:
Number of moles = Mass/molar mass
0.008 mol = 1.28 g / molar mass
Molar mass = 1.28 g / 0.008 mol
Molar mass = 160 g/mol
