Question

With an equilibrium constant of k=1.3 if NaOH and MgCL2 are added in stoichiometric ratio and 1.2 mol of NaOH are present at equilibrium, how much precipitate is produced (in moles)?

Answer 1

MgCl, magnesium and Chlorine

Answer 2

Your addendum makes no sense.
That's k = 1.3 for what. Is is Mg(OH)2? If so 1.3 isn't right. You've made a typo surely.

Answer 3

I'm sorry, I forgot the Chemical Reaction

NaOH(aq)+Mg(Cl)2(aq)<->NaCl(aq)+Mg(OH)2(s)

Answer 4

And the 1.3? What about it?

Answer 5

Equilbrium Constant.