Hello ,
i have this Chemistry thing that i cant do
We've done an experiment to determine the Vitamin C Concentration in Fruit Juice.
* We added 30cm
3 of Potassium iodid and 10cm
3 of sulphuric acid to a conical flask
* Then we added 25cm
3 of Potassium iodate(V) and 25cm
3 of Apple Juice
* Then we Titrate against Sodium thiosulphate , using starch as the indicator
= the result was 5.15 cm
3 Concentration Of :
* iodate = 0.005
* Sodium Thiosulphate = 0.01
OK So the Qs were :
Q1 Calculate The number of moles Of iodate (V) ions Present in 25cm3 of Potassium iodate(V) n of Moles = Mc / 1000
= 0.001 * 25 / 1000 = 2.5 * 10
-5 Mol
Q2 Using the Equation
IO3- + 5I- + 6H+ --> 3I2 3H2O
Calculate the # of Moles Of iodine ProducedSo 2.5 * 10
-5 Multiply By 3
= 7.5 * 10
-5 Mol
Q3 Using Your titre calculate the # of moles of thiosulphate that have reactedn=cV
n= 0.01 * 5.15 = 0.0515 mol
Q4 Using This equation
I2 = S2O32- --> S4O62- + 2I-
Calculate the # Of moles of iodine that have reacted with the thiosulphateIt will be 0.0515 mol
Q5 Use Your ans. from part 2 & 4 to calculate the # of moles of iodine used to oxidise the Vitamin CQ6 Calculate the # of moles of Vitamin C in 25cm3 of Apple JuiceQ7 Given that the molar mass of Vitamin C is 178 then Calculate the concentration of Vitamin C in the apple Juice in g dm-3
How Can i do the last Three Q