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Class 11
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Kinetic Theory
estimate the total number of air molecules inclus...

Question:
Estimate the total number of air molecules (inclusive of oxygen, nitrogen, water vapour and other constituents) in a room of capacity 25.0 m³ at a temperature of 27 °C and 1 atm pressure.

Answer:

Volume of the room, V= 25.0 m³

Temperature of the room, T= 27°C = 300 K

Pressure in the room, P= 1 atm = 1 × 1.013 × 10⁵ Pa

The ideal gas equation relating pressure (P), Volume (V), and absolute temperature (T) can be written as:

PV = k_BNT

Where, K_B is Boltzmann constant = 1.38 × 10^-23 m² kg s^-2K^-1

N is the number of air molecules in the room

∴ N = PV / K_B T

= 1.013 x 10⁵ x 25 / 1.38 x 10^-23 x 300

= 6.11 × 10²⁶ molecules

Therefore, the total number of air molecules in the given room is 6.11 × 10²⁶.

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Question:
Estimate the total number of air molecules (inclusive of oxygen, nitrogen, water vapour and other constituents) in a room of capacity 25.0 m³ at a temperature of 27 °C and 1 atm pressure.

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Question: Estimate the total number of air molecules (inclusive of oxygen, nitrogen, water vapour and other constituents) in a room of capacity 25.0 m3 at a temperature of 27 °C and 1 atm pressure.

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Question:
Estimate the total number of air molecules (inclusive of oxygen, nitrogen, water vapour and other constituents) in a room of capacity 25.0 m³ at a temperature of 27 °C and 1 atm pressure.