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# How many moles.....

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1. How many moles of electrons are there in one mole of OH- Ions? I know the answer but not sure how to go about tackling this question.
2. how many electrons are there in an OH- ion? 10 (I think...)

ratio= 1 OH- : 10 e-

so in 1 mole of OH-, there's 10 moles of e-
3. (Original post by LegendX)
How many moles of electrons are there in one mole of OH- Ions? I know the answer but not sure how to go about tackling this question.
O has 8 electrons so 8 moles
H has 1 electron so 1 mole
the negative sign is +1 electron so another mole which equals 10.
4. (Original post by word2yamother)
You can only get moles of atoms not moles of subatomic particles
Not true

Moles is just the SI unit for amount, so it can be for atoms, ions, molecules, electrons etc.
5. (Original post by word2yamother)
You can only get moles of atoms not moles of subatomic particles
You can get moles of H+ ions, which are protons
6. That's not true.
7. So basically when it says a question like this, you break it down so for example if it said, how many m,es of electrons in SO4 2- charge, it would be

16 electrons frm sulfur
32 electrons from oxygen
And 2 more cus its 2- ?

But I don't understand why the charge on the ion makes you add electrons.
8. (Original post by LegendX)
So basically when it says a question like this, you break it down so for example if it said, how many m,es of electrons in SO4 2- charge, it would be

16 electrons frm sulfur
32 electrons from oxygen
And 2 more cus its 2- ?

But I don't understand why the charge on the ion makes you add electrons.
The -ve charge is due to excess electrons (similarly +ve charge is from a lack of electrons.)

The number of protons doesn't change (otherwise the element would change) but electrons can be lost/gained to give charged ions...
9. (Original post by Hearty_Beast)
The -ve charge is due to excess electrons (similarly +ve charge is from a lack of electrons.)

The number of protons doesn't change (otherwise the element would change) but electrons can be lost/gained to give charged ions...

so the moles of electrons in say ' 2 SO4 2- ' would be:

164?
10. (Original post by LegendX)
so the moles of electrons in say ' 2 SO4 2- ' would be:

164?
S = 16e
Each O = 8e
2- = 2e
SO42- = 16 + (8*4) +2 = 50e

So 2SO42- = 2x50=100e

I think you might have used the mass number of sulfur instead of the atomic number.
11. (Original post by Hearty_Beast)
The -ve charge is due to excess electrons (similarly +ve charge is from a lack of electrons.)

The number of protons doesn't change (otherwise the element would change) but electrons can be lost/gained to give charged ions...
in SO42- where did the excess of 2 electrons come from? if the S supplies 16 electrons and the O supplies 32 electrons surely it would be 48 electrons in total and not 50?
12. (Original post by LegendX)
in SO42- where did the excess of 2 electrons come from? if the S supplies 16 electrons and the O supplies 32 electrons surely it would be 48 electrons in total and not 50?
neutral S provides 16 electrons, neutral O provides 32 electrons

you have a 2- charge on the ion so you have to add 2 more electrons
13. As previously stated, a mole is simply an amount. You could have a mole of moles if you really wanted to. Or a mole of voles if that's more your thing
14. (Original post by illusionz)
As previously stated, a mole is simply an amount. You could have a mole of moles if you really wanted to. Or a mole of voles if that's more your thing
How many mole of particles are there then in one mole of electrons?
15. (Original post by anillatoo)
How many mole of particles are there then in one mole of electrons?
Seeing as electrons are elementary particles (leptons), 1.
16. (Original post by illusionz)
Seeing as electrons are elementary particles (leptons), 1.
Alright, so if I understood your reasoning, one mole of proton contains 3 moles of quarks which each contains one mole of 6.02*10^23 particles?
17. (Original post by anillatoo)
Alright, so if I understood your reasoning, one mole of proton contains 3 moles of quarks which each contains one mole of 6.02*10^23 particles?
Well I wouldn't normally think about it in that way - I only brought up elementary particles because your question seemed rather odd. I guess you could argue that each proton contains 3 quarks so therefore a mole of protons contains 3 moles of particles, but it's not something anyone would ever ask.

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