The correct statement regarding Joule – Thomson effect is ____?

When a real gas is allowed to undergo unrestricted expansion adiabatically, it undergoes cooling except for He and hydrogen. This is called positive Joule-Thompson effect due to the presence of intermolecular forces. This fact find its use in liquefaction of gases.∂T∂PH>0; for most gasesHe and hydrogen experiences heating. This is called negative Joule-Thompson effect∂T∂PH<0; for H2 and HeFor ideal gas,∂T∂PH=0So they do not experience either cooling or heating.