Last Lab

7th semester is around to end with the final term that i.e starting from a week after, before that, we have a paper on the Organic lab of the experiments that we performed throughout the semester.

Last Tuesday we synthetized Benzil from benzoin. Benzoin was already prepared in a lab before. So we weigh 2.4 grams of Benzoin using Electronic balance. Concentrated nitric acid, hot plate, and ice-chilled water are used as chemicals.

I forgot my lab coat and gloves at home, my friend alone was experimenting. Usually, we both collect apparatus and chemicals but I was sitting on the chair and writing practicals in a notebook because precautions are more important. The chemicals we are using are concentrated and may cause damage with a lab coat and gloves. Moreover, I said my friend let girls perform us already performed previous all, let them know about sample handling. But most of the girls are sitting on chairs and busy in gossip.

I was not in the mode of performing because I have written all of the practicals that we performed in the last two were not written on my note as we have not performed these two, When the instructor checked my notebook she asked why you have not written last two practicals. I replied:

"Mam abhi hum ne ye perform nhi kiye iss liy nhi likhy"

Mam said: I told the class to write all of the practicals in the notebook. Sit and complete your notebook. I thought I already performed in the previous labs and let other fellows learn more who are only used to watching what is happening! So I started writing practicals which I completed in 45- minutes. I asked Mam to check my notebook. She checked it out and I am free of any sort of practical notebook work.

My fellows on the other hand perform practical. The sample solution was placed on the hotplate for heating almost for 60-minutes. 55-minutes were completed and I was there to see what was going on. I performed the last step and placed this mixture in Ice-chilled water

For the formation of precipitates, which are not performed. Later we added ice-chilled water to the conical flask containing the reaction mixture. Pre-mature crystal formation started. After that, we took a filter paper and funnel and filter out benzil crystals. The filtration took almost 5-minutes and our next lecture almost started.

We have no time to dry benzil crystal and then weigh it out so placed it directly on an electronic balance and were shocked to see the weight was 7.8 grams because of wet filter paper. We decided to weigh out the benzil crystals when they will completely dry and left. After the next lecture we back again in the lab and weight out the crystals for finding the actual yield. Then the percentage yield obtained was 73%.

Thanks for reading!

@Shani59

26-05-2022