What property doesnt apply to fluids? Newtons second, cons of energy, cons of mass, ideal gas law or all the above do apply? What property doesnt apply to fluids? Newtons second, cons of energy, cons of mass, ideal gas law or all the above do apply? Solution Conservation of energy, conservation of mass and newton\'s 2nd law are never violated. They can be applied any where But ideal gas law is not. It is just an approximation and real fluids will not follow ideal gas law..