Question

10.1g of potassium nitrate were dissolved in 50cm^3 of water. the temperature fell by 16 degrees celsius. Determine
(a) the number of moles of potassium nitrate dissolve in 50cm^3 of water.
(b) heat change that would be produced if one mole of potassium Nitrate dissolve completely in 1 dm^3 of water.
specific heat capacity of water. (4.18 J kg ^-1 degrees C^-1

Answer 1

a) mols = grams/molar mass
b) q = mass H2O x specific heat H2O x delta T
That gives you delta H/10.1 and
delta H/mol = delta H/10.1 g x ( molar mass/1 mol) and convert that to kJ/mol

Answer 2

10.1/50= 0.202