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March 10, 2021

What is CV for a monatomic gas?

What is CV for a monatomic gas?

The molar specific heat capacity of a gas at constant volume (Cv) is the amount of heat required to raise the temperature of 1 mol of the gas by 1 C at the constant volume. Its value for monatomic ideal gas is 3R/2 and the value for diatomic ideal gas is 5R/2.

What is a monatomic ideal gas?

An ideal gas composed of single atoms. Examples include the noble gases argon, krypton, and xenon.

What is r in heat capacity?

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.

Why does pressure cause heat?

An increase in pressure does produce heat. when you apply pressure on a gas enclosed in a cylinder then the gas molecules collide with each other due to small space and collide with piston also. Hence applied work get results into increase in energy of molecules and hence temperature.

Is CV dependent on temperature?

The electron contribution to cv is proportional to temperature, cv el = γT and becomes significant (for metals only) at very low temperatures (remember that contribution of phonons cv ~ AT3 at T → 0K). Rising temperature results in the increase of the average amplitude of atomic vibrations.

What material has the highest specific heat?

Liquid water

Why does heat capacity decrease with temperature?

The heat capacity is the slope of the plot of internal energy U with temperature T. The internal energy is energy that due to the rotation and vibrational energy a molecule possesses and as the temperature increases more rotational and vibrational energy levels becomes excited and so the internal energy increases.

How does heat capacity change?

As the substance heats up, the average kinetic energy of the molecules increases. The collisions impart enough energy to allow rotation to occur. Rotation then contributes to the internal energy and raises the specific heat. The vibrational energy states are farther apart than the rotation energy states.

Can heat capacity be zero?

Zero heat capacity means an infinitesimally small amount of energy will increase the temperature by an infinitely large amount. An object has a non-zero heat capacity because it has internal degrees of freedom that it can channel absorbed energy into.

How does specific heat of water vary with temperature?

Precisely, water has to absorb 4,184 Joules of heat (1 calorie) for the temperature of one kilogram of water to increase 1°C. For comparison sake, it only takes 385 Joules of heat to raise 1 kilogram of copper 1°C.

Why is specific heat of water so high?

Water’s high heat capacity is a property caused by hydrogen bonding among water molecules. When the temperature of water decreases, the hydrogen bonds are formed and release a considerable amount of energy. Water has the highest specific heat capacity of any liquid.

How can you increase the specific heat capacity of water?

Temperature, pressure, phase all affect water at the molecular level and therefore the microscopic manner in which the water will absorb energy. So yes, the heat capacity of water can be increased/decreased by changing the macroscopic conditions (phase, temperature and pressure).