Question 1
Multiple choiceEasy1 markTwo samples of the same gas are at 20.0 °C and 40.0 °C. Which value is closest to the ratio of the average kinetic energy per particle at 40.0 °C to that at 20.0 °C?
Show answer and explanation
Answer: C. For the same gas, average kinetic energy per particle is proportional to temperature in kelvin. Converting gives 293.15 K and 313.15 K, so the ratio is 313.15/293.15 = 1.07.
A: calculates the fractional increase, 20/293.15 ≈ 0.07, rather than the final ratio.
B: reverses the ratio, using 293.15/313.15 ≈ 0.94.
D: uses the Celsius readings directly, giving 40.0/20.0 = 2.00.
Remember: use kelvin values when forming a ratio of temperatures.