Iodide/Iodine

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acid_burn

Aquarium Advice Activist
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Feb 9, 2004
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MI.
I am cofused with these two, are they the same?

My multitest kit measures both like they are the same, it gives only one reading :?

I bought some Seachem Reef Iodide (because it says on the bottle that iodine is as toxic as chlorine and should never be used in a reef aquarium) to raise iodide/iodine for my carpet anemone.

thanks,
Rich
 
the salifert kit I got tested for both but only hte iodide showed up (i htink one or the other) I was confused also. If you do dig up anything post it here so I can know too:)
 
In chemistry the ending on a chemical compound's name indicates whether is is in its elemental state or if it is bonded to something else. It can also indicate the ratios of ingredients in the chemical.

In the case of iodine , the INE ending indicates elemental iodine - in its pure one type of atom form. Pure iodine is toxic as are the rest of the family of elements to which it belongs ( Fluorine, Chlorine, Bromine, Iodine, and Astatine). Fluorine is the most chemically reactive and toxic of the family.

In the case of the IDE ending, the iodine is chemically bonded to another element. When elements bond, the compounds that form have different properties than the elements from which they are made.

Sodium ChlorIDE = Table salt 1 atom sodium + 1 atom of chlorine
Sodium is a metal that will violently explode in water
Chlorine is a yellow green gas that will rip your lungs apart

Put them together and sprinkle it on french fries.

Sodium FluoriIDE = active ingredient in toothpaste

Potassium IodIDE is what is in the reef additives and is also a salt.

1 atom of Potassium bonded to 1 atom of chlorine. When it is dissolved in water, solution is formed.

The term SALT is a word for any compound formed from a group of metals called the Alkali metals and the Family called the Halogens ( to which iodine belongs). Not all of these salts are safe to eat though so don't go sprinking your aquarium chemicals on your scrambled eggs ('8O') !

There is a reason why these particular atoms like each other so much, but unless anyone is truly interested ....... ( I'm a science teacher so I tend to get a little excited about these things(':roll:')

At a retail store you will pay from $7.00 to $12.00 for an 8 ounce bottle of a concentrated KI ( Potassium Iodide ) solution. All that this means is that the water is holding as much of the KI as it can. You will have paid at leat $8.00 for about a nickels worth of material. In fact the packing for the product was probably more costly than the chemicals. I paid $4.00 for 500 grams of KI crsytals. Enough to keep me in solutions for just about forever.

Other common salts that you pay big bucks for in the lfs include:

Strontium Chloride
Calcium Chloride

Again - nothing exotic but definitely overpriced.
 
Well said JG 8O , but i'm still a little confused. So iodide is a chemical compound made from iodine?

I've also seen iodine additive available for reef tanks so now i'm really confused about that. I thought iodine is toxic by itself :?

In the end the iodide i'm adding helps to keep my anemone and corals healthy?

Thanks,
Rich
 
Without getting to "Techy" Iodine belongs to the halogen family on the periodic table. They all end with INE in that family ( Fluorine, chlorine, bromine, and iodine). The INE ending is really just an attempt to keep family members sounding the same. In their pure forms they are always searching for another element from which to "steal" an electron. This is how they form compounds with other elements. I tell my students that they are "bullies" and the metals in the other family I discussed are the "Wimps". The metals like potassium, sodium, and lithium are all looking to get rid of an electron. It's a match made in heaven. The wimps will give the electron to the bullies, but then must hang out together as a compound.

When you see the word Iodine - with the INE ending we are talking about pure iodine , the bully. If you were to place this in your tank, it would begin to steal electrons from anything it can find, changing your water chemistry or harming the tissues of living things.

Whe you see the word IODIDE, we are talking about a bully that has already joined with a wimp and has made a compound. It is "happy", if you will, and has no need to seek out electrons from anyone else in your tank.

Unfortunately, it sounds as if the test kits and their literatures are a bit fuzzy on the actual chemical difference between Iodine and Iodide.

Maybe it might help if you think about the iodine solution that is used by surgeons or when you donate blood. If iodine crystals ( iodine is a grey glossy crystal) are dissolved in alcohol we get Tincture of iodine which is used as a disinfectant when having surgery or stitches. It is a great disinfectant because it is a bully and will destroy the bacteria on skin while taking electrons. You would not want to put this stuff in your tank.

However, potassium iodide is result of a bully wimp pairing and so is not not going to rip apart the tissues of your coral or fish.

BTW, potassium iodide is the same stuff you would be given if you were exposed to radioactive fallout.

These test kits are actually testing for the ions of iodine ( iodine atoms with a extra electron taken from a wimp) that are bonded to the potassium ion ( a potassium atom with one less electron). This electron tapdance changes how the iodine behaves in your tank.

Let me know if this helps.

Joanne
 
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