We’re being asked to determine the enthalpy change (ΔHrxn) for the chemical reaction:
2 M(s) + 3 Cl2(g) → 2 MCl3(s)
We can use Hess’s Law to determine the enthalpy change of the overall reaction from the given reactions:
1. 2 M(s) + 6 HCl(aq) → 2 MCl3(aq) + 3 H2(g) ΔH1 = –579.0 kJ
2. HCl(g) → HCl(aq) ΔH2 = –74.8 kJ
3. H2(g) + Cl2(g) → 2 HCl(g) ΔH3 = –1845.0 kJ
4. MCl3(s) → MCl3(aq) ΔH4 = –141.0 kJ
We now need to find a combination of reactions that when added up, gives us the overall reaction.
Consider these reactions, where M represents a generic metal.
1. 2M (s) + 6HCl (aq) → 2MCl3 (aq) + 3H2 (g) ΔH1 = -579.0 kJ
2. HCl (g) → HCl (aq) ΔH2 = -74.8 kJ
3. H2 (g) + Cl2 (g) → 2HCl (g) ΔH3 = -1845.0 kJ
4. MCl3 (s) → MCl3 (aq) ΔH4 = -141.0 kJ
Use the following information above to determine the enthalpy (kJ) of the following reaction.
2 M(s) + 3Cl2 (g) → 2 MCl3 (s)
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Our tutors have indicated that to solve this problem you will need to apply the Hess's Law concept. You can view video lessons to learn Hess's Law. Or if you need more Hess's Law practice, you can also practice Hess's Law practice problems.
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Our tutors rated the difficulty ofConsider these reactions, where M represents a generic metal...as medium difficulty.
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