Question
An unknown gas weighs 34g and occupies 6.7L at 2 atm and 245K. What is the molecular weight?
Answers
Answered by
GPT 3.5
To find the molecular weight, we can use the ideal gas law equation:
PV = nRT
where:
P = pressure (2 atm)
V = volume (6.7 L)
n = number of moles
R = gas constant (0.0821 L.atm/mol.K)
T = temperature (245 K)
We can rearrange the equation to solve for the number of moles:
n = PV / RT
Substitute in the values:
n = (2 atm * 6.7 L) / (0.0821 L.atm/mol.K * 245 K)
n ≈ 0.563 moles
Now we can calculate the molecular weight using the formula:
Molecular weight = (mass of gas) / (number of moles)
Molecular weight = 34 g / 0.563 moles
Molecular weight ≈ 60.42 g/mol
Therefore, the molecular weight of the unknown gas is approximately 60.42 g/mol.
PV = nRT
where:
P = pressure (2 atm)
V = volume (6.7 L)
n = number of moles
R = gas constant (0.0821 L.atm/mol.K)
T = temperature (245 K)
We can rearrange the equation to solve for the number of moles:
n = PV / RT
Substitute in the values:
n = (2 atm * 6.7 L) / (0.0821 L.atm/mol.K * 245 K)
n ≈ 0.563 moles
Now we can calculate the molecular weight using the formula:
Molecular weight = (mass of gas) / (number of moles)
Molecular weight = 34 g / 0.563 moles
Molecular weight ≈ 60.42 g/mol
Therefore, the molecular weight of the unknown gas is approximately 60.42 g/mol.