First I'd like to say, first post!

And second, there is this (http://www.homedepot.com/h_d1/N-5yc1v/R-202092148/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053) bag of lime at Home Depot. Simply stated, I was wondering if this is the chemical Calcium Hydroxide. Also, is there a possibility that it might contain something else that would not be Calcium Hydroxide? Or is there a way of testing this? My best friend's brother's girlfriend's father's mother's cousin in law twice removed's daughter's teacher has a science project coming up and it very important that it is ONLY Ca(OH)2. I wouldn't want them to ruin their project. And, if this is in the wrong area, feel free to move it. I thought because it was related to a Tek from this site, you guys could help me with my project as it is very, very, VERY similar. Help with that would be highly appreciated!

Just cut the bullshit and order some calcium hydroxide online. It's not watched - that's why people come up with ways to use it instead of lye.

I'm sort of sick of ordering things from online. I buy one thing, then as it's arriving, I realize I need another, and then everything takes weeks to get here when I could have just gone down to the right store and bought some.

Dont get your Lime from The Homey D it isnt what youre looking for.

Get some Mrs Wages Pickling Lime from the market.

Please don't There is no need to incriminate yourself but grammar can be used in a different way than via an absurd social connections circle. Think about it. It's CRYSTAL clear to everybody that the mentioned connection doesn't not exist

As for chemicals I avoid using brands names since formulations change and suppliers disappear thus MSDS (Material Safety Data Sheet). In your case you would click "More info" and then "MSDS".

In the MSDS we see "CHEMICALLY HYDRATED LIME". All good. We move down and look for "CAS No.". It's a special number for every chemical compound. Googling reveals it's calcium hydroxide. Splendid ! But it also has another CAS number, , which is Calcium magnesium hydroxide (I think this name isn't correct chemically but still), which is not our "lime". pH of the mixture is also a little lower (11.7) than that of calcium hydroxide (12.4).

My guess is that this is a mixture of calcium hydroxide and other stuff.

billydgator, have you tried any "lime" from Home Depot ?

Thank you so much Shaolin. That was the sort of answer I was looking for. After some more research I learned that "Cal" from a Mexican store is also Calcium Hydroxide. I don't think it would be the Oxide mainly since they sell it with spices, and it's food grade, ie. meant to be consumed. So I *think* I should be safe there. Correct?

No problem, glad I could help. As for "Cal", only the label can tell. If you're lucky there is an american distributor listed, so you call them and ask if this is 100% calcium hydroxide since you need it for your aquarium

Seems to me like this is easily remedied with a little forethought and something as simple as a "shopping list"...