How do you write a Mass Balance or Charge Balance for Acid-Base Equilibrium?

[jkh4]

Can somebody explain how do you write a Mass Balance or Charge balance for a acid-base equilibrium? Let say, if you are given 0.01M Zn(OH)2 in a saturated NaOH solution and also given that Zn(OH)2 + 2OH- -> Zn(OH)4(2-) how would you solve the mass balance/charge balance? I really have no idea how to do these types of quesitons...Thanks!

 

[chemisttree]

You just did it...

 

[Borek]

http://www.chembuddy.com/?left=balancing-stoichiometry&right=algebraic-method

You may ignore solving part, but writing equations is just creating balances you are asking for.