[pakiaish]

Consider the following balanced thermochemical equation for a reaction sometimes used for
H2S production:
1/8 S8 (s) + H2 (g) → H2S (g) ΔHrxn = -20.2 kJ
(a)Is this an exothermic or endothermic reaction?
(b)What is ΔHrxn for the reverse reaction?
(c)What is ΔH when 3.2 mol of S8 react?

if any one has any explanations for this problem it would be great. thanks

[Donut]

1/8 S8 (s) + H2 (g) → H2S (g) ΔHrxn = -20.2 kJ
(a)Is this an exothermic or endothermic reaction?

As the ΔH is negative the reaction is exothermic.

(b)What is ΔHrxn for the reverse reaction?

Im guessing (dont quote me on this!) that it would require +20.2kJ (ie you put it in) per mole of H₂S to produce 1/8 S8 and H2

(c)What is ΔH when 3.2 mol of S8 react?

Im not sure if you mean 3.2/8 moles of S8 or 3.2 moles of S8. In either case, assuming the stoichiometric relationships were maintained (ie H2 was also increased by a factor 3.2) then the enthalpy change would be multiplied by 3.2

Wait till someone smarter confirms this before you decide to use it