# What is the unit of heat capacity at constant pressure?

## What is the unit of heat capacity at constant pressure?

joule
15.1. In the International System of Units (SI), heat capacity is expressed in the unit of joule(s) (J) per kelvin (K). The unit of kJ/°C is often used in thermal recovery. CV and Cp denote the heat capacity at constant volume and constant pressure, respectively.

What are the units of CV and CP?

CV is the specific heat at constant volume, and CP is the specific heat at constant pressure. Specific heat is the heat energy required to raise the temperature of a substance (per unit mass) by one degree Celsius.

What is specific heat at constant pressure CP?

The values indicated by Cp and Cv are the specific heats of an ideal gas. These indicate the quantity of heat that can increase the temperature of unit mass by 1°C. Hence, the specific heat at a constant pressure is more than specific heat at a constant volume, i.e. Cp > Cv.

### Why is heat capacity higher at pressure?

The heat capacity at constant pressure CP is greater than the heat capacity at constant volume CV , because when heat is added at constant pressure, the substance expands and work. QV = CV △T = △U + W = △U because no work is done. Therefore, dU = CV dT and CV = dU dT .

Which is greater CP or CV?

The molar heat capacity at constant pressure is represented by Cp. At constant pressure, when a gas is heated, work is done to overcome the pressure and there is an expansion in the volume with an increase in the internal energy of the system. Therefore, it can be said that Cp is greater than Cv.

How to calculate heat capacity at constant pressure?

The heat capacity at constant pressure, Cp, is the ratio dq / dT for a process in a closed system with a constant, uniform pressure and with expansion work only. Under these conditions, the heat dq is equal to the enthalpy change dH (Eq. 5.3.7), and we obtain a relation analogous to Eq. 5.6.1: Cp = (∂H ∂T)p Cp is an extensive state function.

## What kind of heat is used in a constant pressure system?

Isobaric heat capacity (Cp) is used for air in a constant pressure (ΔP = 0) system. Isochoric heat capacity (Cv) is used for air in a constant-volume, (= isovolumetric or isometric) closed system.

Which is the specific heat of constant volume?

The specific heat of the object will be different in either case. The former is called the specific heat at constant volume, Cv, whereas the latter is called the specific heat at constant pressure, Cp.

How does heat capacity contribute to thermodynamics?

At constant pressure, heat supplied to the system would contribute to both the work done and the change in internal energy, according to the first law of thermodynamics. The heat capacity would be called