Acetanelide Lab Report

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The initial impure mixture was tan, with large, long crystals that were white or yellow, but after the recrystallization, the pure mixture was white powder with extremely small crystals. Upon testing for the purity through melting point comparison, the melting points were 113.7°C-116.7°C and 113.85°C-116.95°C.
The average temperature is then 113.85°C-116.95°C when the trials were added and divided by two. The actual melting range of pure acetanelide is 113°C-115°C, which means that the melting point of the recovered acetanelide was less than 2°C more than it was supposed to be, which means that there may have been a few minute impurities, but the acetanelide was reasonably pure.

Experiment and Sources of Error: The experiment was followed …show more content…

The buildup may have allowed some of the impurities to get past the filter paper. In order to re-dissolve the solution, the solution was poured form the funnel back into the flask, heated, and re-added. In order to get all of the solution to go through, a large quantity of hot solvent was added on the filter paper to clear the blockage, which caused a large excess of solvent to be present. This may have led to less pure acetanelide forming as crystals, as more acetanelide would stay in the discarded solution. In response to this, the solution, now with more water than intended, was boiled down as time would allow from about 120 ml to about 80 ml, and the experiment was continued with more solute than …show more content…

Before the cold filtration, the solution was in the flask containing the stir bar, but there were impurities adhering to the stir bar that would not come off, and the stir bar could not be removed without losing any solution. This may have caused some impurities to be re-entered into the solution after it was hot vacuum filtered. Another source of experimental error occurred after the cold vacuum filtration, as the dried acetanelide crystals would not come cleanly off the filter paper. A glass rod was used to try to scrape it off, but a bit was lost as it clung to the glass rod and filter. After being allowed to dry for a week, another source of error occurred, as when the crystals were being transferred from the filter paper to the weight boat, a fair amount of acetanelide was spilled onto the table and some would not come off of the filter paper. These crystals’ melting point was then determined, concluding the

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