At What Temperature Is the Rms Speed of Hydrogen Molecules $\mathrm { H } _ { 2 }$

Multiple Choice

At what temperature is the rms speed of hydrogen molecules, $\mathrm { H } _ { 2 }$ which have a molecular weight of 2.02 g/mole, equal to 2.0 km/s? The Boltzmann constant is $1.38 \times 10 ^ { - 23 } \mathrm {~J} / \mathrm { K } \text { and } N _ { \mathrm { A } } = 6.022 \times$ $10^{23}$ molecules/mol.

A) $17 ^ { \circ } \mathrm { C }$
B) $51 ^ { \circ } \mathrm { C }$
C) $72 ^ { \circ } \mathrm { C }$
D) $34 ^ { \circ } \mathrm { C }$
E) $68 ^ { \circ } \mathrm { C }$