Question

The root mean square (rms) speed of oxygen molecules (O₂) at a certain temperature T (degree absolute) is ν. If the temperature is doubled and oxygen gas dissociates in to atomic oxygen. Is the rms speed remains unchanged –

(1) Yes

(2) No.

(3) Nothing can be said

(4) None of these

Answer 1

Correct Answer is: (2) No.

Rootmean square speed v = √3RT /M When temperature is doubled,

the new temperature T’ = 2T and oxygen (O₂) dissociates in atomic oxygen,

then molecular weight M’ =M/2

The new rms speed