At what temperature will sulfur hexafluoride molecules have the same average speed as argon atoms at 20°C?
A)-22.0°C
B)73.2°C
C)381°C
D)799°C

Question

Quizplus · Accepted Answer

The average speed of gas molecules is proportional to the square root of the temperature divided by the molar mass. To have the same average speed, the temperature for sulfur hexafluoride must be higher due to its larger molar mass compared to argon. Calculating this gives approximately 799°C.

At What Temperature Will Sulfur Hexafluoride Molecules Have the Same