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1. A quantity of molecular hydrogen (H2) gas fills a one liter container at a temperature of 200 K and pressure of 1 atm.
What is the average (rms) speed of the molecules?
KE_trans = 1/2 M<v^2>
Energy_trans = 3/2kT = 3/2RT
H2 = 2g/mol
Assuming 1 mol of H2:
mass = .002kg
1/2 M<v^2> = 3/2RT
(.002kg)<v^2> = 3R(200K)
<v^2> = 2494200m/s
Vrms = sqrt(<v^2>) = 1579.30m/s
Which is wrong.
The correct answer is 1600m/s. (Not a rounding error.)
Can anyone help me?
Thanks!
What is the average (rms) speed of the molecules?
Homework Equations
KE_trans = 1/2 M<v^2>
Energy_trans = 3/2kT = 3/2RT
H2 = 2g/mol
The Attempt at a Solution
Assuming 1 mol of H2:
mass = .002kg
1/2 M<v^2> = 3/2RT
(.002kg)<v^2> = 3R(200K)
<v^2> = 2494200m/s
Vrms = sqrt(<v^2>) = 1579.30m/s
Which is wrong.
The correct answer is 1600m/s. (Not a rounding error.)
Can anyone help me?
Thanks!