Which will not appear in the equilibrium constant expression for the reaction below?
H2O(g) + C(s) <->H2(g) + CO(g)
1.[H₂O]
2.[C]
3.[Hz]
4.[CO]
Please help!

[C]

Explanation:

H20 does not appear when it is a liquid because pure water has a concentration of 1. However, you must notice that it is a gas in this problem so it must be entered.

The Reason C is not is because it is a solid. solids also have a concentration of 1 and are not necessary to calculate Ka or Kb

answer : third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol

explanation :

let us write down the given equations

equation 1 :

equation 2 :

equation 3 :

let us use hess's law to find out which 2 equations can be added to get the third equation.

let us reverse equation 2 and multiply it by 2. the new equation that we get is,

equation 4 :

let us add equation 1 & 4

the above equation is similar to equation 3 but has different value for dhrxn.

therefore third trial had the contaminated sample and the correct value for dhrxn should be 1000 kj/mol