A 2.00 L sample of a gas has a mass of 2.92 g, a pressure of 1.3 atm, and a temperature of 243 K. What is the molar mass of this gas?
pv=nRT
solve for n
then n=2.92/molmass solve for molemass.
Im a little confused but I solve for n but the do I divide it by 2.92
Nvm I got it thank you so much
To find the molar mass of a gas, we can use the ideal gas law equation:
PV = nRT
where:
P = pressure of the gas
V = volume of the gas
n = number of moles of the gas
R = ideal gas constant
T = temperature of the gas
We can rearrange this equation to solve for the number of moles (n):
n = (PV) / (RT)
Given:
P = 1.3 atm
V = 2.00 L
T = 243 K
R = 0.0821 L·atm/(mol·K) (the ideal gas constant)
Now, substituting these values into the equation, we get:
n = (1.3 atm * 2.00 L) / (0.0821 L·atm/(mol·K) * 243 K)
Simplifying, we have:
n = 0.6838 mol
The molar mass of a gas is defined as the mass of one mole of the gas. So, to find the molar mass of the gas, we divide the mass of the gas sample by the number of moles (n).
Given:
mass of the gas = 2.92 g
Now, let's calculate the molar mass:
molar mass = mass of the gas / number of moles
= 2.92 g / 0.6838 mol
≈ 4.27 g/mol
Therefore, the molar mass of this gas is approximately 4.27 g/mol.