(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

How much heat will be transferred when 0.54g of sulfur reacts with 0.54g of oxygen to produce sulfur trioxide according to the following reaction:

2 S (s) + 3 O2 (g) --> 2 SO3 (g)

change in Enthalpy = -790kJ

2. Relevant equations

3. The attempt at a solution

First, I reduced the equation:

S + 3/2 O2 --> SO3

change in Enthalpy = -395 kJ/mol

Second, I figured out the limiting reactant:

0.54g x (mol/32.07g) = 0.017mol x (3 mol O2 / 2 mol S) = 0.0253 mol O2

0.54g O2 x (mol/32g) = 0.017mol x (2 mol S / 3 mol O2) = 0.0112 mol S

Third, I took the limiting reactant, 0.0112 mol S, and did:

0.0112 mol S x -395kJ = 4.42kJ

So my answer is 4.42kJ. However, this answer was incorrect. Would anyone be able to guide me to the correct answer? Thanks!!

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# Homework Help: Thermochemistry Problem

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