Today we performed the 3rd on-campus lab of organic chemistry and the assessment was to synthesize Schiff base from, Benzaldehyde, aniline, Ethanol, and acetic acid.

The apparatus used in the experiment was a measuring cylinder of 10ml, conical flask, beaker, pipette, funnel, filter paper, hot plate for heating, Weight balance for the measurement of the product obtained after experimenting as result.

The lab started at 1 pm and when we entered the laboratory, already a class performing there which is almost ended within 10 minutes. Our teacher asked the lab attendant to give us materials either chemical or apparatus, also the class is going on there for our juniors. They were creating noise, which was irritating for our whole class. Because that class shouting in the lab and disturbing others. Also, apparatus and chemicals were present in the cabinet of the lab, it was quite difficult to get to the place where already a class going on.

We are only two boys in our organic chemistry lab while the remaining 23 are girls in the strength of 25 students. We created two groups and started performing the experiment that was, 'the preparation of Schiff Base' we wear the Lab coat, as a safety group, began to collect apparatus and chemicals regarding our experiment. First of all, we took 4ml of concentrated aniline from the stock. Aniline is a locating agent, fumes of aniline were causing suffocation, I was wearing a face mask and prevented harmful impacts of aniline fumes.

Apparatus was gathered but we were unable to find out measuring cylinder of 10ml because we need to measure out the exact concentration of samples. The sample was used in small quantities and 10ml of measuring cylinder was enough for the measurement. I asked the lab attendant for a small measuring and he said, currently no 10 ml measuring cylinder in the lab, you can only use an alternative method of volume determination, then we used a pipette and a sucker for the measurement and put it into the conical.

Firstly we took 1ml of benzaldehyde in a conical using sucker and pipette. In the next step 10ml of ethanol is added to it, 2 ml of acetic acid is put into the conical flask, and in the last aniline of 1 ml is added in the same apparatus. After adding these 4-chemicals shake it well.

Placed the conical flask on the water bath and heat it for 30 minutes at 70-80° temperature. The color of the sample solution was orange-red which remained unaffected after 30-minutes. According to theory crystals should form on heating for 30 minutes by maintaining a specific temperature instead of it solution became more concentrated instead of formation of crystals. If crystals were formed next step was to filter out these crystals using filter paper by the filtration process. Dry out these crystals and find the percentage yield of Schiff base produced.

But after performing the experiment crystal are not formed only the solution became more concentrated. The reason could be improper sample handling, faulty apparatus, or chemicals.

Conclusions:

At last, Mam assigned us an assignment to find out alternative methods for the preparation of Schiff base. I will check in the last lecture and conclude which more effective way for aniline preparation than we will perform it in the Lab.