Which of the following molecules does not exist according to molecular orbital theory?

Root mean square ( rms ) speed of $\mathrm{O}_2$ is $500 \mathrm{~m} / \mathrm{s}$ at a constant temperature. Calculate the rms speed and the average kinetic energy of $\mathrm{H}_2$ at the same temperature. (Consider, $R=8.33 \mathrm{JK}^{-1} \mathrm{~mol}^{-1}$ )

Which of the following describes an ideal gas?

(i) The volume occupied by a gas molecule is negligible.

(ii) The collision between ideal gases are elastic.

(iii) Particles are very small compared to the distance between each other.

What is the $\%$ strength of 22.4 volume of $\mathrm{H}_2 \mathrm{O}_2$ solution?