Lab 2 - Caroline Ho Mixed Melting Points Purpose: In this...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
Caroline Ho Mixed Melting Points Purpose: In this lab, the identity of an unknown compound is confirmed by the technique of mixed melting points of the unknown compound a known compound. Discussion: Part I: Finding an Identical Compound I used the melting point of a mixture to locate another student with an unknown solid identical to mine. This process is called melting point determination. After finding the melting point range of my compound, I searched for people with similar melting ranges, preferably within 4°C of mine. Mixtures of about equal amounts of two compounds are prepared and the melting points of these mixtures are determined. If my compound (A) and the lab partner's compound (X) are identical, the melting point of the mixture of A and X will have the same melting point as the pure compounds, apart from slight differences due to impurities specific to a certain sample. If A and X are different from each other, the melting point of their mixture will be lower than that of either A or X. The first mixture prepared was successful and indicated that the two were identical compounds because the resulting mixed melting point range was 96.2°- 98.1°C, a range that was extremely close to the melting range of my original compound. My mixture with another lab partner resulted in a melting range of 76.3°- 79.5°C. Even if two different compounds have the same melting point, the melting point of the mixture will be lowered because the compounds are no longer pure. Part II: Generation of a Melting Point-Composition Diagram The graph for average temperatures is attached. For 70:30, there was a dramatic difference between the two temperatures. However, none of the data was removed because there were only two data points. For 60:40, student 1's data was removed because it was 10°C higher than the other two data points. For 50:50, student 3's data
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
was removed because it was drastically lower than the other two data points. For
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/08/2009 for the course CHEM Chemistry taught by Professor Nitche during the Spring '08 term at University of California, Berkeley.

Page1 / 4

Lab 2 - Caroline Ho Mixed Melting Points Purpose: In this...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online