At what temperature is the root mean square speed of oxygen molecules equal to the r.m.s. speed of carbon dioxide molecules at `-23^(@)C`? Molecular weight of oxgen=32 and that of carbon dioxide=44.

Options

A. `+91.2^(@)C`
B. `-91.2^(@)C`
C. `+112.2^(@)C`
D. `-112.2^(@)C`

Answer

B

Explanation

`V_(rms)=sqrt((3RT)/(M))=sqrt((3RT)/(32))`
`V'_(rms)=sqrt((3RT)/(M))=sqrt((3Rxx250)/(44))`
`V_(rms)=V'_(rms)`