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Topic: Iodine Numbers  (Read 4102 times)

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Offline CSG

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Iodine Numbers
« on: May 10, 2010, 10:57:58 AM »
Hi,

I understand that the iodine number is the number of moles of iodine reacting with one mole of fat/oil which indicates the number of double bonds present in the fat/oil molecule.

However I am having trouble calculating them.

Can someone show me how to solve the following question please?

0.014 moles of a particular oil was found to react exactly with 14.2g of iodine. Calculate the number of moles of iodine that reacted and state what can be deduced about the structure of the oil from this information.

This is as far as I got:

Number of moles of iodine: 14.2/126.9 = 0.112mol


« Last Edit: May 10, 2010, 11:57:08 AM by CSG »

Offline MOTOBALL

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Re: Iodine Numbers
« Reply #1 on: May 11, 2010, 07:24:24 PM »
Your starting point is the definition of the Iodine number

1 mole of Iodine reacts with 1 mole of fat/oil that contains 1 double bond,

then,

0.112 moles of I2 . 0.112 moles fat that contains 1 DB
0.112 moles of I2...0.014 moles fat that contains 0.112/0.014 = 8 DB

You have 8 x >C=C< in your sample.

Offline Borek

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Re: Iodine Numbers
« Reply #2 on: May 12, 2010, 02:56:50 AM »
Number of moles of iodine: 14.2/126.9 = 0.112mol

As we have already found somewhere else - it is not 0.112, as iodine is not atomic.
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Offline JGK

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Re: Iodine Numbers
« Reply #3 on: May 12, 2010, 02:57:29 PM »
Experience is something you don't get until just after you need it.

Offline MOTOBALL

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Re: Iodine Numbers
« Reply #4 on: May 12, 2010, 07:44:31 PM »
Correction, you have 4 x DB

Mea culpa !!!

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