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प्रश्न
Explain the term mole fraction.
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उत्तर
Mole fraction is the ratio of the number of moles of a particular component of a solution to the total number of moles of the solution.
If a substance ‘A’ dissolves in substance ‘B’ and their number of moles are nA and nB, respectively, then the mole fractions of A and B are given as:
Mole fraction of A = `"Number of moles of A"/ "Number of moles of solution"`
= `n_A/(n_A + n_B)`
Mole fraction of B = `"Number of moles of B"/ "Number of moles of solution"`
= `n_B/(n_A + n_B)`
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| Physical quantity | Unit |
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| (iv) Molality | (d) Unitless |
| (v) Pressure | (e) mol L–1 |
| (vi) Luminous intensity | (f) Candela |
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| (viii) Mass | (h) Nm–1 |
| (i) kg |
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