The standard heat of formation, in kcal / mol of Ba 2 + is : [Given : standard heat of formation of SO 4 2 − ion (aq) = − 216 kcal / mol , Standard heat of crystallisation of BaSO 4 ( s ) = − 4.5

Question

The standard heat of formation, in kcal / mol of Ba 2 + is : [Given : standard heat of formation of SO 4 2 − ​ ion (aq) = − 216 kcal / mol , Standard heat of crystallisation of BaSO 4 ​ ( s ) = − 4.5 kcal / mol , standard heat of formation of BaSO 4 ​ ( s ) = − 349 kcal / mol ] NEET 2025

TestHub · Accepted Answer

​ Δ H crys ​ ( BaSO 4 ​ ) = Δ H f ​ ( BaSO 4 ​ ) − [ Δ H f ​ ( Ba + 2 ) + Δ H f ​ ( SO 4 − 2 ​ ) ] − 4.5 = [ − 349 ] − [ Δ H f ​ ( Ba + 2 ) + ( − 216 ) ] Δ H f ​ ( Ba + 2 ) = − 128.5 kCal mol − 1 ​

Chemistry - Thermochemistry Question with Solution | TestHub

Options:

Doubts & Discussion