Chemistry Practice Problems Hess's Law Practice Problems Solution: Given these reactions:X(s) +1/2 O2(g) → XO(s)H=-63...

🤓 Based on our data, we think this question is relevant for Professor Patterson's class at TXSTATE.

Solution: Given these reactions:X(s) +1/2 O2(g) → XO(s)H=-639.7XCO3(s) → XO(s)+CO2(g)H=+349.7 What is H(rxn) for this reaction?X(s)+1/2 O2(g)+CO2(g) --> XCO3(s) 

Problem

Given these reactions:

X(s) +1/2 O2(g) → XO(s)

H=-639.7

XCO3(s) → XO(s)+CO2(g)

H=+349.7

 

What is H(rxn) for this reaction?

X(s)+1/2 O2(g)+CO2(g) --> XCO3(s)

 

Solution

We’re being asked to determine the enthalpy change (ΔHrxn) for the chemical reaction:


X (s) + 1/2 O(g) + CO(g) XCO3(s)


We can use Hess’s Law to determine the enthalpy change of the overall reaction from the given reactions:


1. X (s)  + 1/2 O2(g) →  XO (s)     ΔH1  =  -639.7

2. XCO(s)  →  XO (s)+CO(g)   ΔH2  =  349.7


Step 1. We now need to find a combination of reactions that when added up, gives us the overall reaction.


Solution BlurView Complete Written Solution