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# URGENT - titration calculations watch

1. I have a mixture of 50cm3 0.02M iodine, 25cm3 1M propanone and 25cm3 2M HCl in a flask
and every 3 mins i took 10cm3 out and titrated it

at 3 minutes i took 10cm3 of the mixture out and quenched it with sodium hydrogen carbonate
then titrated with 0.005M sodium thiosulphate and it took 34.5cm3 to neutralise the iodine

how do i find the concentration of iodine that was neutralised? i know
M1V1 = M2V2 but i dont know the volume of iodine in the 10cm3 sample?

i need to find the concentration of iodine so i can plot conc against time and find the order but im stuck help!
2. halp plz?
i found the moles in 34.5cm3 and it's 1.725 * 10^-4
and the mole ratio in the equation is 2thio : 1iodine
so moles of iodine = 8.625 * 10^-5
volume = 8.625 * 10^-5/ 0.02
= 4.3125 cm3

so conc = moles/ volume
= 0.02/ (4.3125/1000)
=4.6377 mol/dm3

is that right?
3. apronedsamurai
Plantagenet Crown
4. What's this for? you seem to be in a rush lol
5. (Original post by Squishy™)
What's this for? you seem to be in a rush lol
coursework that's due tomorrow dfaoifjoewijdw
6. (Original post by FormallyIndecent)
coursework that's due tomorrow dfaoifjoewijdw
Level?
7. (Original post by Squishy™)
Level?
A2
8. (Original post by FormallyIndecent)
A2
board?
9. (Original post by Squishy™)
board?
OCR B
10. (Original post by FormallyIndecent)
OCR B
I don't know why asking that was necessary, i would do it but its 00:21 n i'm going bed. Soz boss
11. (Original post by Squishy™)
I don't know why asking that was necessary, i would do it but its 00:21 n i'm going bed. Soz boss
kk goodnight
12. bump?
13. Bumping to help out a friend x
14. FormallyIndecent You still need help?

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