Question

If a substance ‘A’ dissolves in a solution of a mixture of ‘B’ and ‘C’ with their respective number of moles as \(n_a\), \(n_b\), and \(n_c\), the mole fraction of C in the solution is:

• A. $\frac{n_C}{n_A + n_B + n_C} \\$
• B. $\frac{n_C}{n_A \times n_B \times n_C}$
• C. $\frac{n_C}{n_A - n_B - n_C} \\$
• D. $\frac{n_B}{n_A + n_B} \\$

Answer 1

The Correct Option is A

Solution: The mole fraction of a component in a solution is the ratio of the moles of that component to the total moles of all components in the solution.

To calculate the mole fraction of C, given the moles of substances as \(n_a\), \(n_b\), and \(n_c\), the total moles in the solution are:

\(n_a + n_b + n_c\).

The mole fraction of substance \(C\) is calculated as:

\(\text{Mole fraction of } C = \frac{n_c}{n_a + n_b + n_c}\).

Conclusion: Consequently, the mole fraction of \(C\) in the solution is represented by option (1): \(\frac{n_c}{n_a + n_b + n_c}\).