When 3.2 g of ammonium chloride is dissolved in 75 g of water, the temperature of the solution decreases from 22.8°C to 20.1°C. What is the energy of dissolution of NH4Cl per mole? (The molecular mass of NH4Cl = 53.49 g/mol, and the specific heat of water = 4.18 J/g°C.)

Question

A. 14.8 kJ/mol
B. 0.88 kJ/mol
C. 390 kJ/mol
D. 125 kJ/mol

Answer 1

Dissolving NH4Cl in H2O is an endothermic solution process. You measure how much it cools the solution by the temperature of the H2O.
q = mass H2O x specific heat H2O x (Tfinal-Tinitial)
The q you measure is for 3.2g/53.4g or q/0.0599 mol. You want to convert that to q/1 mol.

Did you get the Ni/water problem straightened out? I think about 21 (answerD) was the right one? unless I'm not remembering right.

Answer 2

u trippin

Answer 3

u butters fammin - im brod and this webiste pretty ded init hahahahahahahaha. i don't even get half th infor posted- simpligy then explain laterr

Answer 4

24.8