If a substance ‘A’ dissolves in solution of a mixture of ‘B’ and ‘C’ with their respective number of moles as �, � and �. Mole fraction of C in the solution is

Mole Fraction Numerical | Mole Concept | JEE Mains PYQ

Q. If a substance ‘A’ dissolves in solution of a mixture of ‘B’ and ‘C’ with their respective number of moles as n_A, n_B and n_C. Mole fraction of C in the solution is

A. n_C / (n_A × n_B × n_C)

B. n_B / (n_A + n_B)

C. n_C / (n_A + n_B + n_C)

D. n_C / (n_A − n_B)

Explanation

Step 1: Definition of mole fraction

Mole fraction of a component = (Number of moles of that component) / (Total number of moles present)

Step 2: Total number of moles in solution

Total moles = n_A + n_B + n_C

Step 3: Mole fraction of C

Mole fraction of C = n_C / (n_A + n_B + n_C)

Correct Option: C

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