1. If an insoluble impurity, such as sodium sulfate, was present in a sample, wo
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Question
1. If an insoluble impurity, such as sodium sulfate, was present in a sample, would the observed melting point of the sample be too low, too high, or would there be no effect? Explain your reasoning. Explain in detail why the melting point sample should be finely powdered and packed tightly into the capillary tube. 2. 3. Strictly speaking. why is it incorrect to speak of a melting poin? 4. A student has an unknown with an observed melting point of 82.5 -86 . Is it Compound X with a reported melting point of 83.5 -84°C, Compound Y with a reported melting point of 88.s °C-89 °C or Compound Z with a reported melting point of 82 °C-83 C. Explain your reasoning. Page 1 of 2Explanation / Answer
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1)
Any impurity decreases the melting point.
This is because impurities get into the spaces between sample and weakens the intermolecular forces between them. Thus due to weaker intermolecular forces, sample starts to melt at lower temperature
2)
If sample is not powdered nicely, its outer surface will start melting while its inner surface is still intact and not even reached the melting point. SO we can't determone the melting point correctly.
Smapled should be packed tightly to avoid in air in between and heat loses heating them
If sample is powdered and packed tightly, whole of sample will start melting at the same instant.
3)
sample never melt at a particular point. they mely over a range of temperature.
So there should be melting range and not melting point
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