Hess's Law to the following reactions: a) CaO (s) + 2HCl --> CaCl2 + H2O b...

Hess's Law to the following reactions:

a) CaO (s) + 2HCl --> CaCl2 + H2O

b Ca(OH)2 + 2HCl --> CaCl2 + 2H2O

c) CaO (s) + H2O --> Ca(OH)2

Theoretically, which one is the correct relationship for the enthalpy changes of three reactions above?

a) ΔHa = ΔHc - ΔHb b) ΔHa = ΔHc + ΔHb

c) ΔHa = ΔHb - ΔHc d) ΔHa = 2ΔHb + ΔHc

Also explain why the Hess's law applies here by using the first law of thermodynamics?

Expert Solution

queen_honey_blossom answered 2 years ago

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