Question

Compare the kinetic energy of solid, liquid and gas.

Answer 1

1. Kinetic energy can be defined as the energy associated with motion of an object and it is directly proportional to the mass of the object and directly proportional to the square of its speed.
2. The expression for the kinetic energy of an object is, $K=\frac{1}{2}m{v}^2$. Here, $K$ is the kinetic energy, $m$ is the mass and $v$ is the speed.
3. The kinetic energy of molecules primarily depend on their translational and vibrational motion.
4. Solid molecules are bound close to each other and are restricted to vibrational motion. Hence solids will have the least amount of kinetic energy.
5. Liquid molecules can move more freely and hence will also have translational motion. Hence, liquids will have greater amount of kinetic energy than solids.
6. Gas molecules almost act like free particles and hence will have the highest amount of kinetic energy among the three states of matter.

Hence, gases will have the most kinetic energy, liquids have less kinetic energy than gases and solids have the least kinetic energy.