Answer:
The factor by which the average kinetic energy of the oxygen molecules in the cylinder decreases is '0.5'.
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:
\(K=\frac{3RT}{2N_A}\)
where,
K = Average kinetic energy
R = Gas constant
T = Temperature of the system
\(N_A\) = Avogadro's number
Average kinetic energy of oxygen gas molecule at 300 K.
\(K.E=\frac{3R\times 300 K}{2N_A}\)..[1]
Average kinetic energy of oxygen gas molecule at 150 K.
\(K.E'=\frac{3R\times 150 K}{2N_A}\)..[2]
[1] ÷ [2]
\(\frac{K.E}{K.E'}=\frac{\frac{3R\times 300 K}{2N_A}}{\frac{3R\times 150 K}{2N_A}}=\frac{300}{150}=2\)
\(K.E'=0.5\times K.E\)
The factor by which the average kinetic energy of the oxygen molecules in the cylinder decreases is '0.5'.
