In our experiment we tested the amount of vitamin C in a certain amount of lemon juice. We did this with the help of PCPIP which is an indicator that shows the presence if C vitamin. For this we used the mentioned indicator, pipette, three eprouvetes, 0.1% of C vitamin solution and lemon juice.
First we had to get the volume of 0.1% vitamin C solution that is needed for our amount of PCPIP (2ml) to decolorize. Then we had to determine the volume of lemon juice that is needed to decolorize the same amount PCPIP. This provided us with the concentration of vitamin C in the lemon juice.
RESULTS
We got separated into four groups and the results of all of the groups were in the end combined and the average was calculated. Our first result was that the indicator will change the color if we add 0.75 ml of 0.1 % C vitamin solution to it.
We know that 100 ml of the solution contains 0.1 g of vitamin C so with that fact we calculated the amount of grams that can be found in 0.75 ml. We calculated this in the following way:
[pic]
This means that we have 0.75 mg of vitamin C in 0.75 ml of solution. It also means that the indicator (2ml) will turn transparent after we add 0.75 mg of vitamin C.
After that we added lemon juice to the third flask with the indicator. We continued with the addition until the indicator turned transparent. It first turned reddish and after that transparent which we needed. We found out that 2.73 ml of lemon juice is needed in order to turn the indicator transparent. We can conclude that this amount of lemon juice contains the same amount of vitamin C as our previous solution. (0.1% C vitamin solution)
We also wanted to know the amount of vitamin C in a glass of 200 ml which is the size of an average juice glass. We did this in the following way:
[pic]
This means that we have 54.9 mg in an average glass of orange juice. It is also known that the average daily dosage of C vitamin for a person is 60 mg which