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Yes. Let's draw that.
Yeap! The oxygen has six of its own electrons in its outer shell and borrows an electron from both hydrogens to complete its L-shell.
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Well, it has only one electron
in its K-shell (its only shell), so it needs another electron.
I guess it gets one from another hydrogen atom.
You guess right! Hydrogen shares its sole electron with another hydrogen, which shares its sole electron too!Kind of like borrowing from Peter to pay Paul, isn't it? |
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Helium has two protons so it has two electrons to balance the
charge.
But that would mean that it already has a complete K-shell (because the K-shell only holds two electrons). So it doesn't need to share electrons, it has all it needs. Exactly two. Helium wouldn't need to make a covalent bond. |
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Lewis structures.
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Oh, yeah. So, oxygen can share
2 electrons with another oxygen. And that oxygen can share two,
too!
That's right.So, diatomic oxygen is a (elemental) molecule made of two oxygen atoms sharing TWO PAIRS of electrons.Yes. Exactly. Diatomic oxygen is formed by sharing of two pairs of electrons. So how many covalent bonds does it have?Two covalent bonds! One for each pair of shared electrons.Yes, we Alchemists would say each oxygen atom has a "covalency" of two. Hydrogen has a "covalency" of only one. |
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By each sharing 3 electrons
with each other, a total of 6 shared electrons! They form 3 pairs
of shared electrons or 3 covalent bonds. Nitrogen has a covalency
of three! Six electrons are shared in total.
Very good. The bond between these two nitrogens is actually made of three bonds. We call that a triple bond. |
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Anyway, carbon would have
2 electrons in its K-shell and the remaining 4 electrons in its
L-shell. So carbon needs 4 more electrons to give it a complete
L-shell. I suppose it gets them by sharing. Forming 4 covalent
bonds.
That's right. Carbon has 4 electrons to share and needs 4 electrons to complete its L-shell. So it can form 4 covalent bonds. Carbon has a covalency of four.Does it get the other electrons from other carbons? |
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Sure can.
Carbon needs four electrons to complete its L-shell and it will make four covalent bonds to do it. Carbon will share its four electrons to make those bonds, one to each hydrogen. And each hydrogen will share its sole electron with the carbon. So methane is made of a single carbon with four covalent bonds, one to each of four hydrogens. That way the carbon fills its L-shell (taking on the electronic configuration of a noble element). And all 4 of the hydrogens get to share an electron from the carbon, so they can have a complete K-shell (taking on the electron configuration of helium). That's right. Methane has four covalent bonds. Each bond is a "carbon - hydrogen bond". Or simply a "C-H bond". A single covalent bond joins each hydrogen to a central carbon atom, in methane. |
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The carbon will try to form
4 covalent bonds by sharing its four electrons. (Because carbon
has a covalency of four.)
And both oxygens will try to share two electrons, to fill their L-shell. (Oxygen has a covalency of two.) So both oxygen atoms will each form two covalent bonds. Hmm.... My guess is that the carbon forms two covalent bonds with each oxygen. That way everybody is happy. Like this "O=C=O". |
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OK. It has 9 protons and 9 electrons......
Yes, to begin with. But that will change. However, you are right to begin your thinking by starting with a neutral atom. Now where do those electrons go.Ah, 2 into the K-shell and the remaining 7 into the L-shell. It only needs one more to complete its shell. |
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Wait a minute. What do you mean
they "conduct electricity"?
I mean they allow electrons to pass through them easily. Here,
I'll draw it. But I'm not going to draw all the electron shells.
I'll just draw a circle to represent the entire atom and place
its charge inside the sphere.
Kind of like that cat in the village. He wanders around from house
to house, looking for food. But he never stays around for long.
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