Question

Find a case where the convention about signs in thermodynamics, physics, chemistry is not true.

Answer 1

One of the important fact is that physics deals with system and chemistry deals with surroundings.

As per thermodynamics, we have system and surroundings so, we have

Work(System) + Work(surrounding) = Zero

It means when work done by system is positive then work done by surroundings become negative and vice versa

In physics, we calculate forces, acceleration of a body which is a part of system,  Hence System becomes reference in physics. So we give positive sign convention for System and negative to surroundings,

In chemistry,  we calculate temperature, pressure and other properties of the gases which constitutes Surroundings. Hence Surroundings becomes reference in Chemistry. So we give positive sign convention for Surroundings and negative to system in order for the total work done to be zero.