As we know that ideal gas would obey the boyle's law, however, can I say that every gas obeying boyle's law ideal gas?

I have never heard of a realistic gas that obeys any aspect of the ideal gas law as even the molecules in a noble gases are slightly "sticky." The ideal gas law does not take this attractive force into consideration.

On the other hand the noble gases obey the ideal gas law to a good approximation. That's about as good a shot that I can give as an answer to this.

-Dan

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All gases approximately obey the ideal gas law under the righ circumstances. The equation of state for real gases is given by Van der Waals equation

(P + a/V^2)( V - b) = RT

where v and be are constants which depends on the particular gas. At sufficiently large specific volumes (i.e. when the density is low enough) this equation becomes the ideal gas law. a/V^2 arises from the existance of intermolecular forces and b is proportional to the volume occupied by the molecules themselves. At sufficiently large specific volumes, the term a/V^2 becomes neglible in comparison to P and b becomes negligible in comparison to V. The Van der Waals equation then reduces to the equation of state of an ideal gas. This is why the ideal gas law is so useful.


From the above comments one can readily see that if a gase obey's Boyle's law then the density is small enough so that it behaves as an ideal gas. So the answer to your question is - Yes.

At high temperature and low pressure, real gases have ideal behavior.

1)Boyle Temperature by definition is at the temperature at which a real gas exhibits ideal behaviour for an appreciable pressure range.

The expression for Boyle's temperature is a/Rb where a and b are the vanderwaal's parameters of the gas and the R is the gas constant.

An ideal gas as such is a theoretical concept. No gas obeys all the gas laws under all conditions of temperature and pressure. Real gases generally show ideal behaviour at high temperatures and low pressures, when molecular interactions are negligible.

This is because the Kinetic Theory of Gases explicitly assumes that the molecules are mere mass points and donot interact among themselves.
But we know that the molecules of real gases also have some volume and also have interactions.
Hence, the theoretical ideal gas has
1)Higher Pressure
2)Lower Volume
than the real gases.

This is why we have the vanderwaals parameters a and b, which are measures of intermolecular attraction and the effective size of the molecules respectively.

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