Consider an immiscible liquid mixture of n-decane and water containing fully dissociated NaCl. The number of degrees of freedom for this system is
Show Hint
- 3
- 4
- 5
- 2
The Correct Option is A
Solution and Explanation
- In this system:
- Components: \(n\)-decane, water, and NaCl (since NaCl dissociates completely into Na\(^+\) and Cl\(^-\), it still counts as one chemical component). So, \(C = 3\).
- Phases: Two immiscible liquid phases (decane phase + aqueous NaCl solution). Thus, \(P = 2\).
- Applying the phase rule: \[ F = 3 - 2 + 2 = 3 \] - Hence, the number of degrees of freedom is 3. Therefore, option (A) is correct.
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