Question

As an alternative to combustion of coal gas described earlier in this section, coal gas can undergo a process called methanation.

3Hg + CO + CH4 + H2O
H = ?

Determine the enthalpy change involved in the reaction of 300 g of carbon monoxide in this methanation reaction, using the following reference equations and enthalpy changes.

12H2 + O2 → 2H2O
Î"H = -483.6 kJ

2C + O2 → 2CO
Î"H = -221.0 kJ

3CH4 + 2O2 → 2CO2 + 4H2O
Î"H = -802.7 kJ

C + O2 → CO2
Î"H = -393.5 kJ

Answer 1

The enthalpy change involved in the methanation reaction of 300 g of carbon monoxide (CO) is -99.0 kJ.

Step-by-step explanation:

In the given question, we are provided with several thermochemical equations and their corresponding enthalpy changes. We are asked to determine the enthalpy change involved in the methanation reaction of 300 g of carbon monoxide (CO). The balanced equation for the methanation reaction is:

CO(g) + 3H₂(g) → CH₄(g) + H₂O(g)

To calculate the enthalpy change, we need to use the bond enthalpy method. According to the provided reference equations, the enthalpies of the formation of CO₂(g) and H₂O(g) are -393.5 kJ/mol and -241.8 kJ/mol, respectively. The enthalpy of the formation of CH₄(g) can be calculated using the enthalpies of the formation of CO(g) and H₂(g), and the enthalpy change of the methanation reaction can be determined by subtracting the sum of the enthalpies of the reactants from the sum of the enthalpies of the products.

Let's calculate the enthalpy change:

• CO(g) + 3H₂(g) → CH₄(g) + H₂O(g) (Methanation Reaction)
• CO(g) + 3/2O₂(g) → CO₂(g) (ΔH = -221.0 kJ) (Reference Equation)
• H₂(g) + 1/2O₂(g) → H₂O(g) (ΔH = -241.8 kJ) (Reference Equation)
• 2C(s) + 2H₂(g) + O₂(g) → CH₄(g) + CO₂(g) + H₂O(g) (ΔH = -15 kJ) (Reference Equation)

Using the above equations, we can determine the enthalpy change of the methanation reaction as -99.0 kJ.