Question

Among the following, identify the substance in which molecules possess vibratory, rotatory and translatory motions in all directions except in one direction.

• A. bromine
• B. iodine
• C. ammonia
• D. silicon dioxide

Answer 1

The correct option is A

bromine

Reason for the correct option

Bromine$\left(\mathrm{Br}\right)$ is a liquid. So, by having the liquid state the particles in it move faster than in the solid-state. That's why we can say that the molecules of the liquid possess vibratory, rotatory & translatory motions in all directions except in one (upward) direction.

Reason for the incorrect option

B. Iodine$\left(\mathrm{I}\right)$ is a solid that's why it will only possess vibratory motion and rotatory (to a very small extent) motion & does not possess translatory motion.

C. Ammonia$\left({\mathrm{NH}}_3\right)$ is a gas that's why it possesses vibratory, rotatory & translatory motions along with all directions.

D. Silicon dioxide$\left({\mathrm{SiO}}_2\right)$ is also a gas that's why it also possess vibratory, rotatory & translatory motions along with all directions.

Hence option (a ) i.e bromine is correct.