Question

Calculate the change in enthalpy of reaction for each trial, expressed as kilojoules per mole of solid copper (II) chloride dihydrate reacted. Be sure to include the correct sign for ∆H

The copper(II) chloride and aluminum reaction.

Data

Data: Trial 1 Trial2

mass of calorimeter: 8.473g 8.610g

mass of solid Cucl2*2H2O: 3.232g 3.236g

mass of copper solution: 64.594g 62.637g

mass of aluminum foil: 0.814g 0.807g

initial temperature: 19.6C 20.8C

final temperature: 49.2C 53.4C

Answer 1

Trial 1,

Moles of solid CuCl₂.2H₂O = 3.232 / 170.45 = 0.019 (Limiting Reagent)

Moles of Al = 0.814 / 27 = 0.03015

Total Mass = 3.232 + 0.814 + 64.594 = 68.64 g

Specific Heat of Solution = 3.96 J/g-^oC

This is the energy released when 0.019 moles of copper (II) chloride dihydrate reacted with Al. So for 1 mole,

Trial 2,

Moles of solid CuCl₂.2H₂O = 3.236 / 170.45 = 0.019 (Limiting Reagent)

Moles of Al = 0.807 / 27 = 0.0298

Total Mass = 3.236 + 0.807 + 62.637 = 68.68 g

Specific Heat of Solution = 3.96 J/g-^oC

This is the energy released when 0.019 moles of copper (II) chloride dihydrate reacted with Al. So for 1 mole,