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[quote name='somenoobkorean' timestamp='1296103941' post='4964588']
you know i have a feeling there are many arrogant people on this form refusing to ask questions but only answer them instead XD
[/quote]


Lol, I think you're right xD


I would ask questions, but my final tomorrow is APUSH. It's one of those subjects that you don't know what you don't know (if that made sense). So I honestly don't know if i'm prepared or not xD
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[quote name='seattleite' timestamp='1296105068' post='4964635']
It's mostly on content. I'm lucky my teacher doesn't make us memorize dates xD.
[/quote]

lucky you are class was all bout memorizing dates in the miricle of philidelphia damn... pretty much forgot all the dates already except july 4 1977
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Anyone here do chemistry? Minor question on Ionic Bonding (I'm actually best in school at Chemistry/Maths, and in UK Year 11):

We've been told that Non Metals make Positive Ions, and Metals always make Negative Ions.

However, what about Boron (Metaloid)? It only has 3 Electrons in outer shell, so it makes sense for it to lose some, like so:

B ==> [B][sup]3+[/sup].

But as a Metal (Technically) This can't be right...


Also, what about Bismuth (Non Metal). It would much rather gain 3 electrons than lose 5, and would be:

[Bi][sup]3-[/sup].

Which is contradictory.


Finally, and this one is REALLY theoretical, What about Carbon and... Carbon?

If a way of making the energy strong enough was available, would you get [C][sup]4+[/sup] and [C][sup]4-[/sup]?
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I am taking chemistry this year =)

For your first 2 questions, metallic properties actually increase diagonolly across the periodic table. Elements become more metallic down and across.

I *think* that your chemistry teacher was just trying to simplify things down, because youre right, positive and negative ions follow the periodic table more closely than their properties.

For carbon I am not sure. I know of C4 (a plastic explosive), so it is definitely possible. However I don't think Group IV elements react with each other that easily (otherwise you would find them in nature as C2, Si2, etc.)
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[quote name='dogfish44' timestamp='1296667217' post='4981939']
Anyone here do chemistry? Minor question on Ionic Bonding (I'm actually best in school at Chemistry/Maths, and in UK Year 11):

We've been told that Non Metals make Positive Ions, and Metals always make Negative Ions.

However, what about Boron (Metaloid)? It only has 3 Electrons in outer shell, so it makes sense for it to lose some, like so:

B ==> [B][sup]3+[/sup].

But as a Metal (Technically) This can't be right...


Also, what about Bismuth (Non Metal). It would much rather gain 3 electrons than lose 5, and would be:

[Bi][sup]3-[/sup].

Which is contradictory.


Finally, and this one is REALLY theoretical, What about Carbon and... Carbon?

If a way of making the energy strong enough was available, would you get [C][sup]4+[/sup] and [C][sup]4-[/sup]?
[/quote]

Non-metals make NEGATIVE ions (such as O(-2), N(-3), F(-1)), and metals often make cations, or POSITIVE ions (such as Na(+1), Ca(+2)). As long as things aren't in the d orbital (so groups 3 to 12), you usually go by the group it is in. So Boron would love to lose 3, and thus forms a +3 ion. For things in the d orbital, you'd need to refer online unless you want to memorize them all. Iron can form +2 or +3, Silver is a +1, et cetera.

Carbon doesn't usually take part in ionic bonds because it has four bonding positions and thus can form complex hydrocarbons, such as CH4, which don't need ionic bonds. It can form +4 and -4 oxidation states, sure, but it usually doesn't.

I can help people in math and science.
My education goes up to Calc I in math and High School Physics in science. DO NOT ASK ME ABOUT BIOLOGY.

For anybody in Calc II right now, I have this shitty integration problem that I cannot figure out for the life of me.

Imagine a sphere with radius 5 meters. At any given point on the sphere, the density is (5 - x) kilograms per meter cubed, where x is the distance from the center. This means at the center, the density is 5 kg/m^3, and all around the outside, the density is 0. Now, find the mass of the sphere in kilograms.

I know I have to integrate somewhere in this problem, but I'm not sure how to initially set it up.
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kk. Please fill in the App. if you are to answer questions. It just makes it easier.

I am only up to Calculus I, haven't learned integrals yet.


But I have a chemistry question, my teacher didn't give me a straightforward answer: Why do polyatomic ions bond, since they are still ions after bonding?
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[quote name='seattleite' timestamp='1296708098' post='4984190']
kk. Please fill in the App. if you are to answer questions. It just makes it easier.

I am only up to Calculus I, haven't learned integrals yet.


But I have a chemistry question, my teacher didn't give me a straightforward answer: Why do polyatomic ions bond, since they are still ions after bonding?
[/quote]

I filled out the form, but I was Klevar about it.

[i]I can help people in math and science.
My education goes up to Calc I in math and High School Physics in science. DO NOT ASK ME ABOUT BIOLOGY.[/i]

Integrals are in Calc I, but this is like... an "advanced" integral.

No, you are doing this incorrect.

Let's look at Nitrate, or NO3. We know that it has a charge of -1, but that means that somewhere within the single and double and triple bonds of the structure, it was pumped one electron from an "outside" source.

Look at any compound with Nitrate.

Sodium Nitrate... NaNO3.
Calcium Nitrate... Ca(NO3)2.

In both of those, Sodium gives up its one electron to give it to NO3 so it can form Nitrate (because before it gets the electron, it is just... NO3, but kind of unbonded).
Calcium gives up both of its electrons to two different NO3s so they can bond.

Polyatomic ions bond with cations so that they can get the extra electrons to form polyatomic ions with. Kind of get it?
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Well, that was the point I was trying to make.

CO3 and NO3 [b]don't[/b] exist in nature. Polyatomic ions are just a more stable version that carbon and oxygen can form together.

Technically, a fluorine ion with -1 charge does not exist in nature by itself. You see NaF and Ca(F2), and each F does form a -1 ion, but only after it gains an electron from Na or Ca, whatever the cation is.

Saying F(-1) is the same as saying CO3(-1). Neither of them exist purely in nature, but rather bond with cations so they can obtain such a charge.

Carbonate DOES NOT EXIST. Calcium carbonate, sodium carbonate, et cetera, all exist.
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[quote name='Niashi Inumaki' timestamp='1296883284' post='4988846']
Right, right. Sorry. And then ions are elements that have too many protons and anions are elements that have too many electrons, right? Or is that switched..?
[/quote]

Ions are atoms with different number of electrons from the regular atom.
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* Name - You shall never know =o
* Areas of Expertise - Meh, somewhat decent at Maths/Physics/Chem.

[quote name='Niashi Inumaki' timestamp='1296883284' post='4988846']
Right, right. Sorry. And then ions are elements that have too many protons and anions are elements that have too many electrons, right? Or is that switched..?
[/quote]

An ion is anything with a different number of electrons than protons ( a charged atom) . Anions are negative ions. Cations are positive ions. Something with a different number of protons is a different element. Something with a different number of neutrons is a different isotope.
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[i]Imagine a sphere with radius 5 meters. At any given point on the sphere, the density is (5 - x) kilograms per meter cubed, where x is the distance from the center. This means at the center, the density is 5 kg/m^3, and all around the outside, the density is 0. Now, find the mass of the sphere in kilograms.

I know I have to integrate somewhere in this problem, but I'm not sure how to initially set it up. [/i]

Just posting again since I still haven't figured it out.
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