Calculations:
I initially poured 1.10 grams of impure acid into my flask. After the experiment was done, I had 0.54 grams of pure benzoic acid. This gives a difference of 1.10-0.54=0.56 g and a percentage of (0.54/1.10)*100=49.09%
The true melting point of pure benzoic acid is 122.41°C and I received 126.9°C as my melting point. This gives a difference of 126.9°C-122.41°C=4.49°C and a percentage of (122.41/126.9)*100=96.46%
Results:
Impure benzoic acid
1.10g True melting point of benzoic acid
122.41°C
Pure benzoic acid
0.54g Acquired melting point of benzoic acid
126.9°C
Discussion: Each part of this lab was very important. So we needed to have the minimum amount of error to get the right result. The crucial part of this lab was the temperature of the solution and purity of the crystals. By the temperature of the solution I mean that we had to keep the temperature of solution correctly in each part and also to get the melting point …show more content…
(123.2°C -126.9 °C) ! The Idea of recrystallization is to have the minimum solubility (better no solubility) at room temperature but when we heat up the solvent we want the maximum solubility. I tried to get less sand in my first filtration and get all of the crystals from my flask. A source of error might’ve been leftover sand (even after filtration) And the amount of solvent that we had to add to our solution should be right to get the right result. So I added hot water step by step until I got the crystals that I wanted. - If there’s too little, solvent may recrystallize too quickly. - If there’s too much, solvent may not recrystallize at all. So as we cool down the solution, crystals start to occur. Then the slower the material recrystallizes, the better it