Science Buddies: "Ask an Expert"

Hey,

Im doing "how much vitamin C in fruits"

if i add my indicator which is iodine 2% + cornstarch paste its purple...then i just add the juice.

however the problem is i want to know how many grams of vitamin C is in a specific amount of juice.

the only way i can think of is using one or those charts where there is a range or colours from light to dark showing how much so there is of something in a solution. ive done it with Ph levels before but not vitamin C.

ive searched everywhere and answer.com but nothing. i dont know what its called...an indicator chart for vitamin C ?

thanks again to those so consitent in helping me do much project right.
greatly appreciated. thanks

KnightSaber

Hi KnightSaber,

Go look at the 3rd website that jessicahua gave you in the other forum which is: http://www.virtualsciencefair.org/2004/ ... /exp1.html

Then scroll down and look at #8 in the Method section:

8. Line up the tubes from lightest to darkest purple. The lighter the solution, the higher the level of Vitamin C content. That’s because Vitamin causes the purple indicator solution to lose its color.

Or you can look at the 2nd website that jessicahua gave you:
http://www.reachoutmichigan.org/funexpe ... taminc.htm

Scroll all the way down and look at the "Calculations" part. That should help you get the specific amounts of Vitamin C are in different fruit juices.

Hope this helps! Good luck! =)

thanks but what im looking for is actually a chart that shows me the approximate amount of vitamin based on the colour of the solution.

if i was to line then all up from darkest to lightest then i would only be comparing them.

if i was to measure the amount of iodine i put in then it would wreak my experiement since it is a variable im not suppose to be changing. plus i wouldnt know how much iodine is "enough" to make a specific colour.

so therefore i need a chart.

thanks ahmee and jessicahua.

KnightSaber

oops sry for double posting.

is it better if:

i have juice added to iodine.

or

i have iodine added to juice.

im suppose to be testing whats in the juice though....

hi!

I think you should add the juice to the indicator. According to this website: http://www.virtualsciencefair.org/2004/ ... /exp1.html in the methods 5 and 6, it says to put the indicator solution in the test tubes and then add 10 drops of juice to it.

sorry...but I wasn't able to find a chart that would show the amount of Vitamin C. However, if I find one later I will post it.

Have fun with your experiment!