Question

Observe the following reactions: 
\( AB(g) + 25 H_2O(l) \rightarrow AB(H_2S{O_4}) \quad \Delta H = x \, {kJ/mol}^{-1} \) 
\( AB(g) + 50 H_2O(l) \rightarrow AB(H_2SO_4) \quad \Delta H = y \, {kJ/mol}^{-1} \) 
The enthalpy of dilution, \( \Delta H_{dil} \) in kJ/mol\(^{-1}\), is:

• A. \( (y - x) \)
• B. \( (y + x) \)
• C. \( \frac{y}{x} \)
• D. \( \frac{x}{y} \)

Hint:

In thermodynamics, the enthalpy of dilution refers to the change in enthalpy when the volume of the solution increases. It is typically calculated as the difference in enthalpy between the two reactions involved.

Answer 1

The Correct Option is A

We are given two reactions, and the enthalpy change for each reaction is denoted as \( x \) and \( y \).
The enthalpy change for dilution can be obtained from the difference in enthalpy between the second and the first reactions, as dilution refers to the increase in volume, which leads to a change in the enthalpy.
Thus, the enthalpy of dilution \( \Delta H_{dil} \) is: \[ \Delta H_{dil} = y - x \] Thus, the correct option is \( (y - x) \).