8. Thermochemistry
Enthalpy of Formation
8. Thermochemistry Enthalpy of Formation
49PRACTICE PROBLEM
Zinc metal reacts with hydrochloric acid according to the balanced equation:
Zn(s) + 2 HCl(aq) → ZnCl2(aq) + H2(g)
When 0.103 g of Zn(s) is combined with enough HCl to make 50.0 mL of solution in a coffee-cup calorimeter, all of the zinc reacts, raising the temperature of the solution from 22.5°C to 23.7°C. Find ΔHrxn for this reaction as written. (Use 1.0 g/mL for the density of the solution and 4.18 J/g∙°C as the specific heat capacity.)
Zinc metal reacts with hydrochloric acid according to the balanced equation:
Zn(s) + 2 HCl(aq) → ZnCl2(aq) + H2(g)
When 0.103 g of Zn(s) is combined with enough HCl to make 50.0 mL of solution in a coffee-cup calorimeter, all of the zinc reacts, raising the temperature of the solution from 22.5°C to 23.7°C. Find ΔHrxn for this reaction as written. (Use 1.0 g/mL for the density of the solution and 4.18 J/g∙°C as the specific heat capacity.)