Potassium nitrate has a lattice energy of -163.8 kcal/mol and a heat of hydration of -155.5 kcal/mol. How much potassium nitrate has to dissolve in water to absorb 114 kj of heat?

Question

Potassium nitrate has a lattice energy of -163.8 kcal/mol  and a heat of hydration of -155.5 kcal/mol. How much potassium nitrate has to dissolve in water to absorb 114 kj of heat?

bobpursley · Answer

molesKNO3*(lattice energy+hydrationenergy)=114kj solve for molesKNO3

Anonymous · Answer

(-163.8 + - 155.5) = - 319.3 kcal/mol 114kj/319.3 = -0.3570

Anonymous · Answer

Lattice energy is the energy required to for bonds, dH of the solute is the energy required to break the bonds, in other words these 2 are opposites so its should be positive 163.8