The r.m.s. speed of oxygen molecules at 47 is equal to that of the hydrogen molecules kept at . (Mass of oxygen molecule/mass of hydrogen molecule = 32/2)
- -100
- -253
- -20
- -235
Answer
(2) -253
Solution
vrms = 3kBTm
Equal r.m.s. speeds TO2mO2 = TH2mH2
TO2 = 47 + 273 = 320 K
TH2 = 320 232 = 20 K
t = 20 - 273 = -253
Answer: (2)