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Explanation of melting and boiling point deviations

I only need help on question 3.

I have perfomed the labs for melting pt and boiling pt on the following four and only need help with question 3
acetonitrile (C₂H₃N): GIVEN MP = -45.5C, BP = 77.3C
My results MP= -46.8 C, BP = 79.4 C

benzene (C6H6) GIVEN MP = 6.0C, BP = 80.0C
My results MP= 5.4 C BP= 82.5 C

carbon tetrachloride (CCl₄):GIVEN MP = -23.0C, BP = 77.0C
My results MP=-22.3 C, BP -79.4 C

cyclohexane (C6H₁₂): GIVEN MP = 7.0C, BP = 81.0C
My results MP= 6.5 C, BP = 82.7 C

2. For each unknown liquid, record the following:

(b) the percent deviation of each substance, given by:

percent deviation = |(measured value) - (literature value)| / |(literature value)| * 100%

3. Discuss the possible reasons for the discrepancies between the experimental results and the literature values.

Solution Preview

Hello,
Those are actually GREAT experimental results for answering question #3 because they are consistent. Each time, your MP is lower than the given, and your BP is higher than the given. Boiling point elevation and melting point depression are colligative properties, meaning that they depend on the AMOUNT of something ...

Solution Summary

Student presented data from a lab where boiling and melting points were taken and compared to literature values. Student had to explain any deviations. The solution gives a full explanation, as well as sources for further reading.

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