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प्रश्न
If molality of dilute solution is doubled, the value of molal depression constant (Kf) will be ______.
पर्याय
doubled
halved
tripled
unchanged
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उत्तर
If molality of dilute solution is doubled, the value of molal depression constant (Kf) will be unchanged.
Explanation:
The molal depression constant Kf is a property of the solvent only and is defined as
ΔTf = Kf m
Here, Kf depends on the solvent’s nature and not on the solute concentration.
So, even if the molality is doubled, the value of Kf remains unchanged.
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संबंधित प्रश्न
Write the formula to determine the molar mass of a solute using freezing point depresssion method.
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Which of the following statement is false?
Read the passage carefully and answer the questions that follow:
| Henna is investigating the melting point of different salt solutions. She makes a salt solution using 10 mL of water with a known mass of NaCl salt. She puts the salt solution into a freezer and leaves it to freeze. She takes the frozen salt solution out of the freezer and measures the temperature when the frozen salt solution melts. She repeats each experiment. |
| S.No | Mass of the salt used in g |
Melting point in °C | |
| Readings Set 1 | Reading Set 2 | ||
| 1 | 0.3 | -1.9 | -1.9 |
| 2 | 0.4 | -2.5 | -2.6 |
| 3 | 0.5 | -3.0 | -5.5 |
| 4 | 0.6 | -3.8 | -3.8 |
| 5 | 0.8 | -5.1 | -5.0 |
| 6 | 1.0 | -6.4 | -6.3 |
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- One temperature in the second set of results does not fit the pattern. Which temperature is that? Justify your answer.
- Why did Henna collect two sets of results?
- In place of NaCl, if Henna had used glucose, what would have been the melting point of the solution with 0.6 g glucose in it?
OR
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