The H for the solution process when solid sodiumhydroxide dissolves in water is 44.4 KJ/mol.When a 13.9 g sample NaOH dissolves in250.0 grams of water in a coffee cupcalorimeter, the temperature increases from 23.0 oC to______ oC. Assume that the specific heat of the solutionis 4.18 J/g. The H for the solution process when solid sodiumhydroxide dissolves in water is 44.4 KJ/mol.When a 13.9 g sample NaOH dissolves in250.0 grams of water in a coffee cupcalorimeter, the temperature increases from 23.0 oC to______ oC. Assume that the specific heat of the solutionis 4.18 J/g.
Explanation / Answer
We Know that : According toThermodynamical relationship : Q = m x s xt For 1 mole of NaOH when dissolved in water liberates the energy equals to 44.4kJ For13.9 g of NaOH i.e. 13.9 g / 40 g / mol = 0.3475 mol 15429 J = (13.9 + 250 ) g x 4.18 J / g x ( T - 23)0C T = 36.986 0C