Re: did I really get 5% Lugol's??

March 13, 2012

5% simply meand that you have 5 grams of iodine crystals per 100 ml of solution. So for a liter (1000ml) you would have ten times as much or 50 grams of iodine crystals in a liter of 5% lugols.

doug

did I really get 5% Lugol's??

Hi all!

I am really excited!

After 2 weeks of asking here and getting help and looking for where to order on the internet, I suddenly thought I phone the wife of a friend working at the local drug store.

I asked whether I could buy half a liter of Lugol’s 5%, and she said not that many, because she has not that much kalium iodide in the store at the moment.

She asked what 5% meant, I guessed it meant 5% of iodide and iodine measured to the distilled water. She said that’s the double they usually do, but she can do it…

So I got it here already, it says:

10’000 gr Iodum (iodine)

20’000 gr kalii idodidum (kalium iodide)

170’000 gr aqua purificata (distilled water)

I am really bad at arithmetics, but is that not 7, 5%???

Or does the 5% mean sth else?

Can anybody help???

Thanks a lot!

Eva in Budapest

March 13, 2012

I understand, so I really got 5%, and 10’000

g is really 10.000! Got it!

Thank you!

Eva in Budapest

From:

iodine [mailto:iodine ] On Behalf Of polo

Sent: Tuesday, March 13, 2012 4:31

PM

iodine

Subject: Re: did I really

get 5% Lugol's??

5% simply meand that you have 5 grams of iodine crystals per

100 ml of solution. So for a liter (1000ml) you would have ten times as much or

50 grams of iodine crystals in a liter of 5% lugols.

doug

did I

really get 5% Lugol's??

Hi all!

I am really

excited!

After 2

weeks of asking here and getting help and looking for where to order on the

internet, I suddenly thought I phone the wife of a friend working at the local

drug store.

I asked

whether I could buy half a liter of Lugol’s 5%, and she said not that

many, because she has not that much kalium iodide in the store at the moment.

She asked

what 5% meant, I guessed it meant 5% of iodide and iodine measured to the

distilled water. She said that’s the double they usually do, but she can

do it…

So I got it

here already, it says:

10’000

gr Iodum (iodine)

20’000

gr kalii idodidum (kalium iodide)

170’000

gr aqua purificata (distilled water)

I am really

bad at arithmetics, but is that not 7, 5%???

Or does the

5% mean sth else?

Can anybody

help???

Thanks a lot!

Eva in

Budapest

March 14, 2012

Hi

The math to figure your % with Lugol's solution is to add the grams of all the

ingredients, then calculate the fraction of the iodine over the total grams.

So here, you would add

10,000 gr Iodine

20,000 gr Potassium Iodide

170,000 gr water

The total is 200,000 grams. 10,000 divided by 200,000 = .05.

So it is 5%.

Karyn

>

> Hi all!

>

> I am really excited!

>

> After 2 weeks of asking here and getting help and looking for where to order

> on the internet, I suddenly thought I phone the wife of a friend working at

> the local drug store.

>

> I asked whether I could buy half a liter of Lugol's 5%, and she said not

> that many, because she has not that much kalium iodide in the store at the

> moment.

>

> She asked what 5% meant, I guessed it meant 5% of iodide and iodine measured

> to the distilled water. She said that's the double they usually do, but she

> can do it.

>

> So I got it here already, it says:

>

> 10'000 gr Iodum (iodine)

>

> 20'000 gr kalii idodidum (kalium iodide)

>

> 170'000 gr aqua purificata (distilled water)

>

> I am really bad at arithmetics, but is that not 7, 5%???

>

> Or does the 5% mean sth else?

>

> Can anybody help???

>

> Thanks a lot!

>

> Eva in Budapest

>

March 14, 2012

No, don't think that is right. The Potassium Iodide is not really considered

in a 5% solution of lugols, only the iodine crystals.

A percentage solution is figured by grams added per 100 ml, so to make a 5%

solution, one would add 5 grams of solute to a 100ml beaker, then add only

enough water to bring the water level to 100 ml with the dry chemicals in

place. You would be using less than 100ml of water to get the 5%.

To analyze your formula of 10,000 gr of iodine to 170,000 grams of water.

Lets do some conversions. 1 gram of water = 1 ml of water. Thus we are

talking about 170,000 ml of water. 100 ml goes into 170,000 ml at approx

1700 times. Thus you would need to multiply 1700 x 5 grams = 8500 grams of

iodine crystals to make a 5% solution. NOT 10,000 grams! Also, it is

important to consider that one would first add the 8500 grams of iodine and

the 17,000 grams of KI to a container, than only enough water to come up to

a 170,000 ml mark, if such a mark existed in such a large beaker. So,

actually, it would take less than 170,000ml of water as the dry chemicals

take up space in the solution, reducing the amount of water needed.

Lastly, from a 1905 edition of THE PHARMACOPEIA OF THE UNITED STATES, the

following formula for 5% Lugols is given:

Iodine..............5 gm