When enthyne is passed through a red hot tube, then formation of benzene takes place:
`Delta_(f)H_((C_(2)H_(2))(g))^(Theta) = 230 kJ mol^(-1)`
`Delta_(f)H_((C_(6)H_(6))(g))^(Theta) = 85kJ mol^(-1)`
Calculate the standard heat of trimerisation of ethyne to benzene:
`3C_(2)H_(2)(g) rarr C_(6)H_(6)(g)`

Options

A. `205 kJ mol^(-1)`
B. `605 kJ mol^(-1)`
C. `-605 kJ mol^(-1)`
D. `-205 kJ mol^(-1)`

Explanation

To calculate the standard heat of trimerization of ethyne (C₂H₂) to benzene (C₆H₆), we can use the given standard enthalpy of formation values for both compounds.

The reaction we are considering is:
\[ 3 \text{C}_2\text{H}_2(g) \rightarrow \text{C}_6\text{H}_6(g) \]

### Step 1: Write the formula for the enthalpy change (ΔH) of the reaction
The standard heat of reaction can be calculated using the following formula:
\[
...