## anonymous 3 years ago why heat capacity integrals required for accurate enthalpy measurements??????

1. anonymous

No clue what you're talking about.

2. anonymous

How are you going to calculate heat from changes in temperature? Surely something like this:$Q = \int d{\rm T} \thinspace m \thinspace C_p({\rm T})$

3. anonymous

i am talking about enthalpy measurement using the relation$dH=Cp*dT$ and then integrating it over the range of temperature, well acually enthalpy is supposed to be a function of temp. and pressure. at constant pressure if i want to calculate the enthalpy at constant pressure ............. well never mind..!! this was a question in physical chemistry by castellan. i was not able to figure out what might be the answer but now i know the ans.. so u may forget this question.!! the ans is ridiculously simple.. the heat capacity at constant pressure of a substance is not independent of temp. but is a function of temp. so we dont take it as a constant quantity and thus for ACCURATE measurements we use heat capacity integrals.(not from the formula u mentioned carl) but from this formula$Cp=a+bT+cT^2+dT^3+.......$ i hope its a bit clear now// apologies for writing such a long answer!!

4. anonymous