What is an example of an ideal gas?

Answer 1

Any gas can be assumed to be an ideal gas, but no gas really ever is. Assuming a gas is mathematically approximate to an ideal gas if the gas is under a low pressure (<10 Bar), at a low temperature (<1000K), and is not subject to inter-attractive forces (ie a non-polar gas, although the pressure and temperature are bigger considerations)

Thus a great example, is Helium gas at STP (273.15 K and 1.000 Bar)

Answer 2

Nearly all gases have very close to normal ideal behavior. It is really only at high pressures and low temperatures that the behavior of gases varies much from that predicted by the ideal gas law. Something like helium is going to have the closest to ideal gase behavior because it is very small and because its atoms don't tend to interact with each other.

Answer 3

Any gas that abides by the Ideal Gas law.

When someone tells you that something is an idea gas (as for a problem or example), they are implying that for the purposes of
that problem, the behavior of the gas is ideal, i.e. it abides by
PV=nRT.

Answer 4

helium