[joyabraham]

How much is the heat of reaction for AlF3 + 3H2O «→» Al(OH)3 + 3HF

[Borek]

Please read the forum rules. You have to show your attempts at answering the question/solving the problem to receive help, it is a forum policy.

[joyabraham]

I checked many websites but could not find the answer or guidance. One website has a calculator, but unfortunately it has no AlF3 in the list of reactants to choose from.

[Borek]

Just use the Hess's law, enthalpies of formation of all compounds listed are trivial to find.

[joyabraham]

I am unable to calculate using Hess or other chemistry laws and unable to find the answer (the number) from internet, hence asked this help.

[Orcio_87]

I am unable to calculate using Hess or other chemistry laws

Hess law states that enthalpy of the reaction is equal enthalpy of products minus enthalpy of reagents.

[joyabraham]

Thank you for the advice. Enthalpy of Al(OH)3 is not found in any site in internet. If anybody has the answer to my question for this reaction AlF3 (l) + 3H2O (g)→ Al(OH)3 (l) + 3HF (g) kindly give. Whatever guidance provided by earlier replies did not help.

[Borek]

Enthalpy of Al(OH)3 is not found in any site in internet.

Googling for "Aluminum hydroxide enthalpy of formation" got me the answer in no time.

[joyabraham]

Does anybody know if this is an exothermic or endothermic reaction?

[Orcio_87]

True, but joyabraham asks for a liquid (melted) AlF₃ and Al(OH)₃, so this requires additional data to find (heat capacities and enthalpies of melting).

[Corribus]

Heat of formation for liquid AlF3 can be found here.

https://webbook.nist.gov/cgi/cbook.cgi?ID=C7784181&Units=SI&Mask=2#Thermo-Condensed

Usual procedure is to assume these values are invariant over temperature. And in any case the temperature isn't specified, so high precision isn't possible anyway.

Come on, this is just laziness.