Some chemistry/calculus questions?

Question

1. Do the constant volume and constant pressure heat capacities apply for solids and liquids or for gases/(ideal gases?) only?

2. In calculus, what is the difference between d and (delta)? Using entropy, what would be the difference between dS and (delta)S. Also what does the backward looking "6" represent in partial derivatives {ex: partial f/partial x when you have f(x,y)}?

3. How is calculating (delta)H and (delta)U different for solids and liquids that it is for ideal gases?

Answer 1

1. No, they do not. They are for gas only.

2. In calculus, Δx means small but finite change or variation in x, while dx means infinitesimal change or variation in x. Using entropy, ΔS means change of S (now this is chemistry), while dS means infinitesimal change or variation in S. ∂f/∂x means partial derivative of f(x,y) with respect to x (as if y is a constant).

3. Sorry this case-to-case discussion. Again in chemistry, ΔH and ΔU is the change in enthalpy and internal energy. They do not have to be small at all.