[pkeller]

Li+Li-(s) → Li(s) + Li(s)

Now consider these reactions and energies:

(i) Li(s) → Li(g), with ΔH = 161 kJ / mol
(ii) Li(g) → Li+(g) + e−, with ΔH = 520.3 kJ / mol
(iii) Li(g) + e− → Li− (g), with ΔH = −56 kJ / mol
(iv) Li+Li− (s) → Li+(g) + Li− (g), with ΔH = 734.7 kJ / mol

Use this information to calculate ΔH for the dilithium destruction reaction below.

Li+Li− (s) Li(s) + Li(s)

 

[G O D I V A]

I believe that you gotta do hess's law and I get +109.4 kJ/mol?  Is that correct?

[pkeller]

I believe that you gotta do hess's law and I get +109.4 kJ/mol?  Is that correct?

yes I think thats the right aswer, could you show how you rearranged the state equations that were given to cancel out. I cant get them to cancel for some reason

[G O D I V A]

Red is 520.3
Purple is 734.7
Cyan is -56
Black is 161

Red is wrong way so becomes -520.3
Purple is correct way
cyan is wrong way which becomes 56
Black si wrong way which becomes -161

therefore:

-520.3 + 734.7 + 56 - 161 = +109.4 kJ/mol

[pkeller]

Thanks.