Discussion Lab Experiment 4 Lipid 50fb

Discussion Experiment 4: Lipid In this experiment, we are able to determine the saponification number for each sample tested. Saponification value (sap) or also known as saponification number represents the number of milligrams of potassium hydroxide (KOH) required to saponify 1g of fat under the conditions specified. It measures the average molecular weight of all the fatty acids present. The smaller the molar mass of the fat, the higher the saponification value. In this experiment we obtained that there are three different values of saponification number for butter that we get from three different groups. There are slight different between the readings which are 84.2, 98.2 and 14.0 respectively. There are huge different between the readings due to technical errors. This might due to addition of too much phenolphthalein into the sample solution. Secondly, the readings are not taken immediately after the solution turned colorless. Butter fat is made out of a majority of short chained fatty acids, hence it should have high number of saponification value. Margarine have higher number of saponification value which is 84.2, followed by sunflower oil sap value of 33.7, corn oil sap value of 28.1 and palm oil sap value of 28.1. Theoretically triglycerides containing long fatty acids will have a lower saponification number than triglycerides with shorter fatty acids. Low fatty acid fats like coconut oil or palm oil fat will have high saponification value. On the other hand vegetable oils like sunflower oil will have a lower saponification number. It means that, palm oil have the shorter fatty acid chain than corn oil and sunflower oil. For the palm oil and corn oil, the saponification number should higher than sunflower oil because they have shorter fatty acid chain than sunflower oil. Due to errors during experiment, the results obtained were totally different from what we expected. The amount of phenolphthalein dropped into the solution might be too much or too little hence it alters our value of amount of HCL.

Reflection (Yuri) In this experiment, we need to find the value saponification number for each of the sample. Different groups were assigned with different type of samples. I also feel so thrilled to learn how to make soap by using modern ingredients. We were assigned to bring some decoration from home for instance flowers, perfume, glitters and so on. The process of determining the saponification number required many steps. Hence, my groupmates and I divided the work equally. We are so lucky that we are able to finish the experiment within the time given.

I’m glad that our instructor being so helpful and this make our experiment run smoothly. Last but not least, a massive respect to my group for contributing their hard work in order to make this lab work a success. Thank you.