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Topic: 4 questions need help  (Read 3933 times)

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Offline michaels234

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4 questions need help
« on: May 14, 2007, 06:51:16 PM »
I can't seem to find the answers to any of these questions and my teacher is too busy to help so can someone find the answers to these 4 questions.

1. What is the affect of ammonia's lone pair of electrons on it's bond angles?

2. How do London forces get stronger as molecules get larger?

3. What's hydrogen's role in creating the charges found in polyatomic ions?

4. Why does cesium have such a low melting point?

Offline syko sykes

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Re: 4 questions need help
« Reply #1 on: May 14, 2007, 07:56:55 PM »
1. with most any compound, unbonded electrons take up more space pushing the other bonds closer together. i forget the name but i think NH3 would look like a tripod for this reason

3. hydrogen is usually a +1 charge
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Offline constant thinker

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Re: 4 questions need help
« Reply #2 on: May 14, 2007, 09:34:01 PM »
1. Read up on Valence Shell Electron Pair Repulsion Theory (VSEPR).

2. Think about what causes London Forces. Larger molecules have more electrons usually.

3. A number of polyatomic ions start off as oxyacids. Example sulfate (SO4-2) comes from sulfuric acid which is H2SO4. The difference between the sulfate ion and sulfuric acid is the 2 hydrogen atoms.

[Edit] I'm trying to lead you in the right direction instead of just citing the 4th rule of forum rules, which is what I usually do when someone hasn't shown their attempt.
« Last Edit: May 16, 2007, 08:21:51 PM by constant thinker »
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Offline michaels234

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Re: 4 questions need help
« Reply #3 on: May 15, 2007, 12:09:41 AM »
So no one could find number 4 and the answers you gave me are a little hard to understand.

Offline Mitch

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Re: 4 questions need help
« Reply #4 on: May 15, 2007, 12:42:36 AM »
Your suppose to show you've at least attempted the problem!
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