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Learn About the Molar Specific Heat Capacity

The molar heat capacity of a chemical substance is defined as the amount of energy that must be given to one mole of the substance in the form of heat in order to create a one-unit increase in its temperature.

Have you ever observed that when you are out on the beach, the water is chilly but the sand is hot? This is a common occurrence. If the sun is the same everywhere, what is the cause of the temperature difference? You must have given it some consideration! When we apply heat to a solid or liquid element, the temperature of the element increases. If we apply the same quantity of heat to two distinct kinds of solids, the temperature rise in each of the solids may be different from the other. As a result, the temperature rise for different types of solids varies depending on the composition of the solid. Specific heat capacity is the term used to describe this phenomenon.

Definition

In other terms, the specific heat of a solid or liquid is the amount of heat required to raise the temperature of a unit mass of the solid or liquid by one degree Celsius. C is the symbol we use to represent it. The amount of heat required to raise the temperature of one kilogramme of solid or liquid by one degree Celsius is measured in S.I units.

Its unit of measure in the S.I system is always given as J kg-1 K-1, while its unit of measure in the CGS system is always supplied as cal g-1 C-1. If the quantity of heat, q, required to raise the temperature of a mass M through a temperature difference, ∆T, is known, then the specific heat formula is as follows:

C= ∆Q/m*∆T 

or 

∆Q=m C ∆T

Molar Specific Heat

The Molar specific heat of a solid or liquid of a material is the amount of heat required to increase the temperature of one mole of solid or liquid by one Kelvin (or one degree Celsius) of the substance. C is the letter that we use to symbolise it. Its unit of measure is J mol-1K-1. Consequently, to raise the temperature of a mole of solid through a temperature difference of ∆T, you would require an amount of heat equal to Q=µC ∆T.

When you talk about the molar specific heat capacity of a substance, what you are really talking about is the amount of heat you need to deliver in order to raise the temperature of one gramme molecule of the substance by one degree Celsius. It is symbolised by the letter C. It is assumed that the specific heat of water is one. This is due to the fact that we defined a unit of heat (calorie) by utilising water in our calculations.

Specific Heat at Constant Pressure or Volume

When a solid is heated over a narrow range of temperatures, the volume of the solid remains constant. Specific heat at a constant volume is the term used to describe this. CV is the abbreviation for Cv.

When a solid is heated over a narrow range of temperatures, the pressure of the material remains constant. This is referred to as specific heat at constant pressure (CP), and it can be written as CP.

The way in which gas is heated determines the behaviour of the gas when heat is applied, as well as the pressure and volume changes in temperature, as well as the amount of heat necessary to raise the temperature of 1gm of gas by 1 degree Celsius. To heat the gas, you can experiment with different combinations of P and V values.

As a result, the specific heat has an infinite range of values. If you do not deliver a constant amount of heat to the gas, the specific heat of the gas will not remain constant. As a result, specific heat must be present at a constant volume or pressure. In the case of an ideal gas,

CP – CV = nR

Heat capacity at constant pressure (CP) is equal to heat capacity at constant volume (CV), n is the amount of substance (a), and R=8.3144598(48) J mol-1 K and is the constant of the molar gas.

Applications

The utensils that are used in the kitchen are made of a material with a low specific heat. You have the ability to instantly heat their bottoms. This is due to the fact that their bottoms are polished aluminium or copper. The handle of these utensils is made of a high specific heat material, which allows them to withstand the heat while also protecting our hands.

Insulators are constructed from materials with a high specific heat. Take, for instance, wood. Houses constructed of wood are more suitable for use in high- or low-temperature environments.

Because of the high specific heat of water in the swimming pool, the water used to be relatively cool when compared to the surrounding temperature.

Conclusion

The molar heat capacity of a chemical substance is defined as the amount of energy that must be given to one mole of the substance in the form of heat in order to create a one-unit increase in its temperature. Additionally, it is the heat capacity of a sample of the substance divided by the amount of substance in the sample; or, alternatively, it is the specific heat capacity of the substance multiplied by its molar mass; or, finally, it is The molar heat capacity of a substance, particularly a gas, can be tested and shown to be much larger when the sample is allowed to expand while being heated (at constant pressure, or isobaric) than when the sample is heated in a closed vessel that prohibits expansion (at constant volume, or isochoric). The heat capacity ratio between the two, on the other hand, is the same as that determined from the equivalent specific heat capacities.

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What is the specific heat capacity formula?

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