# Enthalpy change of chromate-dichromate reaction

I am a uni study doing chemistry. I have taken a little bit in highschool before, but not in a while.

In a (nonassessed) practical, we have to predict how heating a chromate/dichromate solution:

$$\ce{2CrO4^2- + 2H+ <=> Cr2O7^2- + H2O}$$

will affect its equilibrium position. However we have not been given its enthalpy, and I can't find it online anywhere.

I remember from highschool that when you don't know an enthalpy you can estimate it by using heats of formation, heats of combustion, or bond energies. However I have never had to do this with an equilibrium of ions in solution before. Can the same approaches still be taken?

Please provide an explanation of how I can estimate the enthalpy change. Quantitative data would be greatly appreciated.

• 1) It's not a forum but Q&A site (Yes, there is some difference) 2) If you had thermodynamic parameters for this you'd be able to calculate what happens not predict. 3) It's about how temperature in general affects reactions, in this case condensations. – Mithoron Feb 23 '17 at 12:27
• @Mithoron Could you explain 3. in more detail? – leob Feb 23 '17 at 23:58