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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: ProblemSets on April 11, 2007, 11:46:46 AM

Title: bromine
Post by: ProblemSets on April 11, 2007, 11:46:46 AM
is solid bromine more dense than liquid bromine??
Title: Re: bromine
Post by: Tomtom on April 11, 2007, 12:42:01 PM
Yes. I believe all solids are more dense than liquids.

For denseness:

Solid>Liquid>Gas
Title: Re: bromine
Post by: Dan on April 11, 2007, 12:45:12 PM
Yes. I believe all solids are more dense than liquids.

Really? Why is an ice cube floating in my glass of water?

In the case of bromine, I expect that the solid is more dense than the liquid.
Title: Re: bromine
Post by: Tomtom on April 11, 2007, 01:51:37 PM
You are of course, completely right; My bad! I can't believe I said what did!

I believe Bromine is, unlike water (which is rather special). It does not expand when it freezes. Therefore, it's density will increase when solid.
Title: Re: bromine
Post by: Dan on April 11, 2007, 04:37:30 PM
Yes, almost all substances do contract when they freeze (ie become more dense).

Notable exceptions besides water ase bismuth and antimony.
Title: Re: bromine
Post by: exec on April 12, 2007, 03:39:20 AM
Water contracts when ice melts because of hydrogen bondings.

In the form of ice, molecules are arranged in such a way that number of H-bonds are maximized. Due to this many bonds, there are a lot of space amongst them which results in higher volume in the ice form, and thus lower density.

When ice melts, some of the H-bonds are broken so that molecules can arrange themselves more compact together. This results in a reduction of volume(reduction of space previously due to H-bonds), and thus an increase in density.

For the case of bromine, there doesn't seem to be any reasons for it to become denser in the liquid form, so your statement should be correct.
Title: Re: bromine
Post by: billnotgatez on April 12, 2007, 06:34:34 AM
exec - what about 
Quote
bismuth and antimony
?