A solution is prepared by mixing 2.0 mol of hexane (C6H14) with 3.0 mol of heptane (C7H16), assuming ideal behavior. What is the mole fraction of hexane in the solution?

• A. 0.60
• B. 0.67
• C. 0.33
• D. 0.40

Answer: (D)

Verified step by step guidance

1. Identify the components in the solution: hexane (C6H14) and heptane (C7H16), with given amounts of 2.0 mol and 3.0 mol respectively.
2. Recall that the mole fraction of a component is defined as the ratio of the moles of that component to the total moles of all components in the solution. The formula is: \(X_{\text{hexane}} = \frac{n_{\text{hexane}}}{n_{\text{hexane}} + n_{\text{heptane}}}\).
3. Substitute the given values into the formula: \(X_{\text{hexane}} = \frac{2.0}{2.0 + 3.0}\).
4. Calculate the denominator by adding the moles of hexane and heptane to find the total moles in the solution.
5. Divide the moles of hexane by the total moles to find the mole fraction of hexane in the solution.