Q1: The heat capacity of a substance is

ANS:A - greater for liquid state than for solid state.

The correct statement is: "higher for solid state than for liquid state." Heat capacity (𝐶C) is the amount of heat required to raise the temperature of a substance by one degree Celsius (or one Kelvin). It's typically expressed in units of energy per degree per mass or per mole. Here's why the heat capacity is higher for the solid state compared to the liquid state:

1. Solid State: In solids, the atoms or molecules are tightly packed and have limited freedom of movement. When heat is added to a solid, this energy is primarily used to increase the vibrational and rotational motion of the atoms or molecules within their fixed positions in the solid lattice. Because the motion is limited, a significant amount of energy is required to increase the temperature.
2. Liquid State: In liquids, the atoms or molecules have more freedom of movement compared to solids. When heat is added to a liquid, this energy is used to increase the translational, vibrational, and rotational motion of the molecules, but they are not constrained to fixed positions as in solids. Therefore, less energy is required to increase the temperature of a liquid compared to a solid.
3. Gaseous State: In gases, the molecules have even greater freedom of movement compared to liquids and solids. When heat is added to a gas, this energy is used to increase the translational, vibrational, and rotational motion of the molecules, which are not constrained by any fixed positions or intermolecular forces. Therefore, gases typically have the highest heat capacity among the three states of matter.