Question

At what temperature will the total $KE$ of $0.3mol$ of $He$ be the same as the total $KE$ of $0.40mol$ of $Ar$ at $400K$?

• A. 533 $K$
• B. 400 $K$
• C. 346 $K$
• D. 300 $K$

Answer 1

The correct option is A 533 $K$

As we know,

$KE$ = $\frac{3}{2}nRT$

$n_1{T}_1=n_2{T}_2$

0.3 $\times T_1=0.4\times 400$

$T=533.33K$