Sample of argon & krypton gas both have same temperature.Which of the following is true regarding argon atoms?

A.The argon atoms have the same average kinetic energy as the krypton atoms, but the argon atoms (on average) are moving faster than the krypton atoms.


B.The argon atoms have the same average kinetic energy as the krypton atoms and therefore have the same average speed as the krypton atoms.


C.The argon atoms have the same average kinetic energy as the krypton atoms, but the argon atoms (on average) are moving slower than the krypton atoms.


D.The argon atoms have the same average speed as the krypton atoms, but the argon atoms (on average) have more kinetic than the krypton atoms.


E.The argon atoms have the same average speed as the krypton atoms, but the argon atoms (on average) have less kinetic than the krypton atoms.Sample of argon %26amp; krypton gas both have same temperature.Which of the following is true regarding argon atoms?
At the same temperature two different gasses will have the same average kinetic energy. Since kinetic energy is calculated from the mass and the square of the speed the most massive particle will have the slowest average speed. Krypton atoms have more mass than argon atoms so argon will have the greater average speed. The answer is A.