Explain the concept of absolute zero of temperature on the basis of ki

1.	Explain the concept of absolute zero of temperature on the basis of kinetic theory of gases.
Answer» According to kinetic theory of gases, the pressure p exerted by one mole of an ideal gas is given by: p = 1/3 M/v C² Or, pV = 1/3 MC² ...(i) (pV = RT) or, C² = 3RT/M or C² ∝ T (R an M are constants) or, C² ∝ √T or √T ∝ C Thus, the square root of the absolute temperature of an ideal gas is directly proportional to root mean square velocity of its molecules: From (i), we have wnen T = 0, C = 0 Hence, absolute zero of the temperature may be defined as that temperature at which the root mean square velocity of the gas molecules reduces to zero. It means molecular motion ceases at absolute zero. It is important to note that this definition holds in case of an ideal or a perfect gas. The gases used in actual practice are far from being perfect, particularly at very low temperatures.

Explain the concept of absolute zero of temperature on the basis of kinetic theory of gases.

Answer»

According to kinetic theory of gases, the pressure p exerted by one mole of an ideal gas is given by:

p = 1/3 M/v C²

Or, pV = 1/3 MC² ...(i)

(pV = RT)

or, C² = 3RT/M or C² ∝ T

(R an M are constants)

or, C² ∝ √T or √T ∝ C

Thus, the square root of the absolute temperature of an ideal gas is directly proportional to root mean square velocity of its molecules:

From (i), we have wnen T = 0, C = 0

Hence, absolute zero of the temperature may be defined as that temperature at which the root mean square velocity of the gas molecules reduces to zero.

It means molecular motion ceases at absolute zero.

It is important to note that this definition holds in case of an ideal or a perfect gas. The gases used in actual practice are far from being perfect, particularly at very low temperatures.

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