Question

Anyone who fast can see how this is true (electroneutrality principle):

Answer 1

Electroneutrality principle:
\[\sum_{i}^{}q _{i}(+)+\sum_{i}^{}q _{i}(-)=0\]
And the equation:
\[[H ^{+}]=[A ^{-}] + [OH ^{-}]\]
In here is q ions and A- any strong acid.

I want to put a 2 infront of [H+] so it give 0 but not sure.

Answer 2

I don't get where your second equation comes from, can you detail?

Answer 3

As a matter of fact. No. my chem prof said that the second equation obay the first... however I can't see it is true.

Answer 4

I mean all the equation say is that in chemical reactions the charge is conserved, but i don't see how we conclude that for the second.

Answer 5

if A- is the only ion in the solution then OK.

Answer 6

The second equation only says the concentration of H+ equals the sum of the concentrations of OH- and A-.

Answer 7

Just don't understand why he write the following: "We set up the equation [H + ]=[A − ]+[OH − ] due to the electroneutrality principle.
So the equation is going to be solved so that the concentration of protons is equal to the amount of strong acid with its proton lost and hydroxide? In that way our equaion follow the electroneutrality principle becuase the charge for the full system then become 0?

Answer 8

Kinda make more sense that way.

Answer 9

basicaly the concentration in pure water is [H+]=[OH-]
then you add AH that dissociates in A- and H+ in equal concentration.
in the end you get [H+]=[HO-]+[A-]
just [H+] is not the same in line 1 and 3...

Answer 10

Oh yea... another way to think of it.

Answer 11

however the first line is only true for T=298 K :P

Answer 12

;-)

Answer 13

Soooo many veriables... can't wait to the day the Theory of Everything for Biology is made..