What Temperature Equals Hydrogen's RMS Velocity to Oxygen's at 300K?

[mit_hacker]

Homework Statement

(Q) Hydrogen molecules have a mass of 2u and oxygen molecules have a mass of 32u, where u is defined as an atomic mass unit (u = 1.660540 \times 10^{-27}\; {\rm kg}). Compare a gas of hydrogen molecules to a gas of oxygen molecules.

At what gas temperature T_rms would the root-mean-square (rms) speed of a hydrogen molecule be equal to that of an oxygen molecule in a gas at 300 K?
State your answer numerically, in kelvins, to the nearest integer.

Homework Equations

v = sqrt(3kT/m) where k is Boltzmann's constant.

The Attempt at a Solution

Using the above equation gives that Temperature is 300/16 = 18.75K. I know that this is a crazy answer but please don't laugh

What's wrong with my solution?

 

[HallsofIvy]

I'll promise not to laugh if you will tell me why 18.75 K is a "crazy answer"!

 

[mit_hacker]

Because...

Thats almost close to absolute 0 and when i fed the answer in, it said "not quite" which I rake to be a euphemism for "this is nonsense!"

 

[jeffsong]

the question requests the "the nearest integer" your result is correct, but I think the anwser should be 19