Calculate δHrxn for the following reaction: c(s)+h2o(g)→co(g)+h2(g)

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Question: Calculate δHrxn for the following reaction: c(s)+h2o(g)→co(g)+h2(g)

use the following reactions and given δh values:
c(s)+o2(g)→co2(g), δh= -393.5 kj
2co(g)+o2(g)→2co2(g), δh= -566.0 kj
2h2(g)+o2(g)→2h2o(g), δh= -483.6 kj

This is a classic Hess' Law question. Your job is to rearrange the three given reactions so that they add up to (and cancel to) the target reaction.

Keep Reaction 1 as is.
Reverse Reaction 2 and cut in half.
Reverse Reaction 3 and cut in half.

c(s)+o2(g)→co2(g), δh= -393.5 kj
co2(g)→co(g)+0.5 o2(g), δh= +283.0 kj
​h2o(g)→h2(g)+0.5 o2(g), δh= +241.8 kj
Added together:
c(s)+h2o(g)→co(g)+h2(g)
Total enthalpy: -393.5 + 283.0 + 241.8 = +131.3 kJ