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In which sample do molecules have the greatest average kinetic energy? A.) He at 100 K. B.) H2 at 200 K. C.) O2 at 300 K. D.) H2O at 400 K.

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D.) H2O at 400 K, it doesn't really matter what the compound is, but only its temperature. Temperature is the average kinetic energy of the sample that we take, so the highest temperature indicates the greatest average kinetic energy.
User Jrief
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Answer: D.)
H_2O at 400 K.

Step-by-step explanation:

Kinetic energy is the energy possessed by an object by virtue of its motion.

Average kinetic energy is defined as the average of the kinetic energies of all the particles present in a system. It is determined by the equation:


K=(3RT)/(2)

K= kinetic energy

R= gas constant

T= temperature in Kelvin

From above, it is visible that kinetic energy is directly related to the temperature of the system. So, if temperature is more, average kinetic energy of the system is more.

Thus
H_2O at 400 K will have greatest average kinetic energy.

User AgeDeO
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