Question

Calculate the total KE of the mixture of 4 gm H₂ and 4 gm He at 300 K –

• A. 1800 R
• B. 1750 R
• C. 1950 R
• D. None

Answer 1

Answer: (C)

1950 R

Answer 2

U = $\frac{5}{2}$ × $\frac{4}{2}$ R × 300 + $\frac{3}{2}$ × $\frac{4}{4}$ R × 300

= $\left( 5R + \frac{3}{2}R \right)$ × 300 = $\frac{13R}{2}$ × 300 = 1950 R