Question

At which of the following temperatures is the average kinetic energy of the molecules of a substance the greatest?

( a. 18.1 °C

( b. 20.4 °C

( c. 36.2 °C

( d. 65.4 °C

Answer 1

D. The higher the temperature the more the atoms are shifting and shaking around

Answer 2

Answer:  $65.4^0C$

Explanation:

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:

$K=\frac{3RT}{2}$

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 and vice-versa.

a. $18^0C=18+273=291K$

b. $20.4^0C=20.4+273=293.4K$

c. $36.2^0C=36.2+273=309.2K$

d. $65.4^0C=65.4+273=338.4K$

Thus substance at $65.4^0C$ will have greatest kinetic energy.