20 Physics -- Ideal Gas

The pressure of a gas at -173C temperature is 1 atmosphere, keeping the volume constant, to what temperature should the gas be heated so that its pressure becomes 2 atm?

1 Answers

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At Initial state

p_i= 1atm

T₀=-173^oc =100k

v_i=v

Finally

P_f= 2 atm

T_f= ?

V_f = v(constant)

By ideal gas law

PV = nRT

V = T/P = constant

T_i/p_i = T_f/p_f

T_f= T_i*P_f /p_i

=100*2/1

= 200k = -73^oc

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Following are the differences betweenr real gases and ideal gases:

Real Gases	Ideal Gases
Real gases follow gas laws under conditions of low pressure and high temperature.	Ideal gases follow gas laws under all conditions of temperature and pressure.
They have intermolecular forces of attraction.	They have negligible intermolecular force of attraction.
Collision of molecules of real gases are not perfectly elastic.	Collisions of molecules of real gases are perfectly elastic.

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Explanation:

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R in the above equation stands for Universal Gas Constant whose value is a constant 8.314 J/mol-K for all gases.

However, when we put n = M/m where M represents total mass of gas present and m the molar mass of the gas.

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What mass of air exists in a 5 x 6 x 8 m³ room at 20°C? Take the average molecular mass of air to be 28 kg K-1 mol-1.

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The postulates of kinetic theory of gas can be found here State the main postulates for Kinetic theory (askmattrab.com).

The condition for a gas to behave as an ideal gas can be found hereA student needed to use the ideal gas for a (askmattrab.com)

Helium gas occupies a volume of 0.04m^3 at a pressure of 2 x 10^5 Nm^-2 and temperature 300K. Calculate the mass of the helium and root mean square speed of its molecules. [ Relative molecular mass...

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A kilogram of hydrogen is having more molecules.

Explanation:
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Calculate the pressure in mm of mercury exerted by hydrogen gas if the number if moles per cm^3 is 6.8x10^15 and the root mean square speed of the molecules is 1.9x10^3m/s. [Avogadros constant = 6....

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Now at T = 0 K, kinetic energy=0

Therefore, the molecular motion is also zero.

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