Guest

How could s​ign convections of work done by the system and work done on the system be different in physics and chemistry

How could s​ign convections of work done by the system and work done on the system be different in physics and chemistry

Grade:12

2 Answers

grenade
2061 Points
8 years ago
it's just a convention in physics we are more interested in getting some work output say a mechanical device , engine etc while in chemistry we are more concerned with the internal energy things so we do so in both the cases the result is same physics case : du = dq - dw , doing work on system increases ineternal energy as dw = negative for work donw on system and vice versa chem case : du = dq + dw ; doing work on system will increase the internal energy of the system as dw = positive which is obvious and vice versa we can take any sign convention in a given problem but we should be consistent with that throughout the problem to avoid confusion and mistake
Gman Namg
415 Points
8 years ago
Alright, in chemistry, we are concerned about the stability of the products. Thus, when work is done by reactants, if it's negative, meaning energy is lost and the products are more stable than the reactants. In physics, we are more concerned about the energy we can harness from a process. So, when work is done by a system, say a Carnot engine, it is taken to be positive and we can use this energy to do useful work.

Think You Can Provide A Better Answer ?

ASK QUESTION

Get your questions answered by the expert for free