[kaseli]

If a carbon has 4 covalent bonds, and two of its electrons (one covalent bond) get taken away, why doesn't the carbocation have a charge of 2+?  I always just see a + written next to it.  Shouldn't it be 2+?

[Benzene]

in methane CH₄ each covalent bond shares one electron with Carbon and one electron with Hydrogen.

so you are correct in noticing that a CH₃⁺ molecule has only 6 valence electrons, not 8.

but since the covalent bond missing was a shared electron pair, the carbon has only lost one electron.

I hope that helps

[kaseli]

in methane CH₄ each covalent bond shares one electron with Carbon and one electron with Hydrogen.

so you are correct in noticing that a CH₃⁺ molecule has only 6 valence electrons, not 8.

but since the covalent bond missing was a shared electron pair, the carbon has only lost one electron.

I hope that helps

That does *delete me*  I knew it had to be simple, I just couldn't figure out how to think about it in the right way.  Thanks so much.

[megaqwerter]

IMHO, it's misleading a little bit.
The total number of electrons in CH4 is 6+4 = 10, the total positive charge of nuclei is 6 + 4 = 10. When we eliminate 1 H with the electron pair we have positive charge 6+3=9 and negative charge 6+4-2=8, hence, the total charge of CH3 is +1. In other words, when you eliminate 1 H with an electron pair you eliminate 1 proton too,

[kaseli]

First of all why does my post say *delete me*. it should say "That does h e l p !"  Weird, anyway..

IMHO, it's misleading a little bit.
The total number of electrons in CH4 is 6+4 = 10, the total positive charge of nuclei is 6 + 4 = 10. When we eliminate 1 H with the electron pair we have positive charge 6+3=9 and negative charge 6+4-2=8, hence, the total charge of CH3 is +1. In other words, when you eliminate 1 H with an electron pair you eliminate 1 proton too,

I had thought about this idea, but quickly dismissed it thinking there would be way too many protons for some reason in secondary and tertiary carbocations.  However, I just drew them out and counted everything up and you are exactly right.  Thanks for your help

[CrimpJiggler]

If you pull off a hydrogen atom from methane, both electrons from the bond go to carbon (this process is known as deprotonation), but you'll still have a 1+ carbocation because one of the electrons belonged to carbon from the start so carbon only actually gained one new electron.

Something else you should know are ionisation energies, they tell you how easy it is to take an electron off a molecule. The energy required make a +1 carbocation, thats called first ionization energy. If you wanted to take another electron to make a +2 cation, then you'd need to check out the second ionization energy. Check out some first and second ionization tables. You'll notice that it takes way more energy to form a +2 cation than a +1 cation. This is due, obviously to electrostatic repulsion between the 2 charges. In other words carbocations with a +2 charge like you described are rare and unstable, so you're not gonna see much of that in organic chemistry.