Question

What does a high specific heat tell about a substance?

Answer 1

The basic heat capacity of a material in thermodynamics is the heat capacity of a sample of the substance separated by the mass of the sample. Informally, it is the quantity of energy that must be applied to one unit of mass of a material in the form of heat in order to produce a one unit rise in temperature.

Complete answer:
As a material, especially a gas, is able to expand as it is heated (specific heat capacity at constant pressure), its specific heat capacity can be substantially higher than when heated in a closed vessel that prevents expansion (specific heat capacity at constant volume). The basic heat capacity of a material is normally measured by calculating the heat capacity of a sample of the substance, generally with a calorimeter, and dividing by the sample's mass. Several methods, such as rapid differential scanning calorimetry, can be used to estimate a substance's heat power.
A high real heat indicates that a substance's temperature is difficult to adjust.
The specific heat potential of a substance is the amount of heat energy it can store per kilogramme per kelvin.
A high specific heat potential ensures that it can store a huge volume of thermal energy with a small change in mass or temperature. It is also effective at retaining thermal efficiency, for example, if an object has a maximum heat capacity of $1\;{\rm{kJ}}\;{\rm{k}}{{\rm{g}}^{ - 1}}\;{{\rm{K}}^{ - 1}}$ . Then it will retain 1kJ of thermal energy for every 1 K of temperature rise, or it will hold for every drop of temperature at a constant mass.

Note:
Instead, it is standard practise to calculate the specific heat capacity at constant pressure (allowing the material to expand or contract as desired), independently assess the coefficient of thermal expansion and compressibility of the material, and then compute the specific heat capacity at constant volume using thermodynamic rules.