Step 1: Understanding the Concept:
Average translational kinetic energy of a gas molecule is \(E_1 = \frac32kT\), where \(k = \frac{R}{N}\). The electron gains \(E_2 = eV\).
Step 2: Equate:
\[ \frac32\cdot\frac{R}{N}T = eV \Rightarrow T = \frac{2eVN}{3R} \]
Here N is the Avogadro-type number of molecules per mole and R is the gas constant, so \(\frac RN\) is the Boltzmann constant.
Final Answer:
The temperature is \(\frac{2eVN}{3R}\), option (B).
\[ \boxed{T = \frac{2eVN}{3R}} \]