First Law of Thermodynamics

Any energy change can be decomposed into contributions from heat and work. This fact is important enough that to be labeled the First Law of Thermodynamics.

[@zulqarnainchaughtai]

I wonder why the academic channels which explain concepts in depth go underrated on KZbin.

[@PhysicalChemistry]

Probably for the same reason that novels sell more copies than textbooks. It takes much more work to follow a lecture than to watch a music video.

[@borutoxg_27]

You can say that again... He is one of the best

[@scienceidisolated6659]

YOU EXPLANATION IS AMAMZING .

[@PhysicalChemistry]

Thanks!

[@abcd0038]

Sir if we heat an liquid and as a result volume increases.thus we can say that the ∆u=q-w.

[@abcd0038]

Since +q is because of transfer of energy into the liquid.

[@abcd0038]

-w is because of the expansion of liquid when heated.since w=-Pext . (∆v),vf is greater than vi as it is expansion process.so w =-p∆v

[@abcd0038]

Is it correct sir?

[@PhysicalChemistry]

Well, I would say ΔU = q + w, probably because I'm using a different sign convention than you are. But yes, the first law of thermodynamics always holds, including for heating liquids.

[@PhysicalChemistry]

Yes, the sign of q will be positive when a liquid is heated, because energy is transfered into the system in the form of heat. (But q always shows up with a positive sign in the first law, ΔU = q + w.)

[@aussiedog5221]

Dr Stuart is excellent instructor.