How Do I Calculate the Enthalpy of Isooctane at 500 K?

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To calculate the enthalpy of isooctane at 500 K, start from the standard state at 278 K and 1 atm. The enthalpy can be determined by calculating it up to the boiling point, then adding the latent heat of vaporization, and subsequently calculating the enthalpy to 500 K using the formula h = mCpΔT. It is important to consider whether to use a constant value for Cp or if it varies with temperature. The original question lacks specific constraints, so additional details would clarify the calculation approach. Providing the complete problem statement will help in giving a more accurate solution.
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I have to calculate the enthalpy of isooctane at 500 K.

Isooctane is a liquid at room temperature and whenever enthalpy is to be calculated, it is from the standard state (278 K temperataure, 1 atm pressure).

Do I calculate enthalpy upto boiling point, then use latent heat of vaporization and from that point calculate enthalpy upto 500 K using h = mCpΔT ? And if so, do I use the same value of Cp throughout?
 
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What's the question say? Is it specific? Free form? Approximate?
 
It says to calculate the enthalpy of isooctane at 500 K on a kJ/kmol basis
 
You haven't been given any constraints beyond units, so you are free to do as you wish.
 
You haven't given the exact and complete problem statement.
 
Can you post the question again with more information ?
 
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