Magnesium nitrate

[rae]

I need to make up 0.1M Magnesium nitrate. The problem is my solid magnesium nitrate is under water. How do I do this?
Any ideas??

Lorrae

[dime]

Are you sure its Magnesium Nitrate under water? The reason I ask is Magnesium Chloride is very hydroscopic. My magnesium nitrate is not new but still chrystalline. But either way, I would still weight out the appropriate amount, water and all. It is for high school and therefore probably not too drastic if not entirely correct.

[jo lindsay]

Our magnesium nitrate is older as well and is still crystallized, but it is hydroscopic (absorbs water) as well. I would do my best to weigh out the amount needed, other than that order some new chemical, i know this is costly. All the best!

[dime]

Oops...I meant hygroscopic. Yeah ...absorbs water.