We know that in isothermal process - T -0 which implies Q - W- My doubt is that Q also equals nC - T and - T -0 due to which Q should be equal to zero and W as well-please resolve my confusion

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Standard XII

Chemistry

Heat and Work

We know that ...

Question

We know that in isothermal process ΔT=0 which implies Q=W. My doubt is that Q also equals nCΔT and ΔT=0 due to which Q should be equal to zero and W as well.please resolve my confusion

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Solution

As we know work is
W= so in isothermal process if we keep temperature constant there will be change in volume and pressure.
PV=nRT T constant so
PV = constant so when we draw this equation we can see that it is a hyperbolic graph and it has area under the curve means it is a bounded function.so there is some work done.so work done can't be zero.and the formula of Q= nc∆T is not working for all thermodynamics process it has some limitations.but the internal energy always depends on temperature.
hope this helps:)

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(d) Q = W

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