# Question: Does CP Depend On Pressure?

## How do you prove CP CV R?

Show that Cp – Cv = R.

Consider one mole of an ideal gas enclosed in a cylinder fitted with movable frictionless piston.

Let the gas be heated at constant volume first.

Let the temperature of the gas increase by dT when dQ quantity of heat is supplied..

## Does specific heat depend on pressure?

depend on pressure as well as on temperature, and the above relations will not all apply. In this respect, the ideal gas is a very special model. In summary, the specific heats are thermodynamic properties and can be used even if the processes are not constant pressure or constant volume.

## Does CP depend on temperature?

In general, the specific heat also depends on the temperature. The table below lists representative values of specific heat for various substances. Except for gases, the temperature and volume dependence of the specific heat of most substances is weak.

## Why is CP is greater than CV?

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.

## Does the specific heat of water increase with temperature?

Some substances heat up quickly, while other substances heat up slowly. Water is one of the latter—it has a high specific heat capacity because it requires more energy to raise the temperature.

## What is the ratio of CP CV?

The heat capacity at constant volume, Cv, is the derivative of the internal energy with respect to the temperature, so for our monoatomic gas, Cv = 3/2 R. The heat capacity at constant pressure can be estimated because the difference between the molar Cp and Cv is R; Cp – Cv = R.

## Can CP be less than CV?

Cp is greater than the molar specific heat at constant volume Cv because energy must now be supplied not only to raise the temperature of the gas but also for the gas to do work. … More heat would be required at constant pressure to cause the same temperature rise and Cp will be greater than Cv.

## Which type of ideal gas will have the largest value for CP CV?

Answer. Cp – Cv will be same for all ideal gases.

## Is CP constant for ideal gas?

For monatomic ideal gases, CV and CP are independent of temperature. … For many purposes they can be taken to be constant over rather wide temperature ranges. For real substances, CV is a weak function of volume, and CP is a weak function of pressure.

## How do you calculate CP at different temperatures?

Note!For ordinary calculations – a value of specific heat cp = 1.0 kJ/kg K (equal to kJ/kg oC) or 0.24 Btu(IT)/lb °F – is normally accurate enough.For higher accuracy – a value of Cp = 1.006 kJ/kg K (equal to kJ/kg oC) or 0.2403 Btu(IT)/lb °F – is better.

## How do you calculate CP of air?

The nominal values used for air at 300 K are CP = 1.00 kJ/kg. K, Cv = 0.718 kJ/kg. K,, and k = 1.4.

## What material has the highest specific heat?

Liquid waterLiquid water has one of the highest specific heats among common substances, about 4182 J/(K kg) at 20 °C; but that of ice just below 0 °C is only 2093 J/(K kg). The specific heats of iron, granite, and hydrogen gas are about 449, 790, and 14300 J/(K kg), respectively.

## What is CP minus CV?

In Section 8.1 we pointed out that the heat capacity at constant pressure must be greater than the heat capacity at constant volume. We also showed that, for an ideal gas, CP = CV + R, where these refer to the molar heat capacities.

## What is CP and CV?

In thermodynamics, the heat capacity ratio or ratio of specific heat capacities (Cp:Cv) is also known as the adiabatic index. It is the ratio of two specific heat capacities, Cp and Cv is given by: The Heat Capacity at Constant Pressure (Cp)/ Heat capacity at Constant Volume(Cv)

## What has a higher specific heat than water?

On a mass basis hydrogen gas has more than three times the specific heat as water under normal laboratory conditions. Diatomic gases under ambient conditions generally have a molar specific heat of about 7cal/(mol K), and one mole of hydrogen has only 2g mass. Thus 3.5cal/(g K) for hydrogen versus 1cal/(g K) for water.

## Does specific heat capacity of water change with pressure?

3 Answers. For water and most solids/liquids, yes but very slightly. When you heat the water it expands, which does work against the surrounding pressure. At higher pressure, the expansion takes more work.

## What is CP for water?

Specific Heat of Water For liquid at room temperature and pressure, the value of specific heat capacity (Cp) is approximately 4.2 J/g°C. … This (1 cal/g. deg) is the specific heat of the water as a liquid or specific heat capacity of liquid water.

## What is CP for ideal gas?

The ratio of the specific heats γ = CP/CV is a factor in adiabatic engine processes and in determining the speed of sound in a gas. This ratio γ = 1.66 for an ideal monoatomic gas and γ = 1.4 for air, which is predominantly a diatomic gas.