[Jacksincy123]

Need help with a past paper question and i have an exam tomorrow.

Ammonia (NH3) dissociates in water to form ammonium (NH4)^+ and hydroxide (OH^-) ions and k = 1.8x10^-5

How much (NH4)^+ is present in a 1M solution of NH3 in water and what is the pH?

Any help would be great  .

P.s new to forums so if im doing anything wrong let me know 

[sjb]

What equations do you know that may help? What does k mean?

[Jacksincy123]

NH3 + H2O = (NH4)^+ + OH^- and k is the equilibrium constant

thanks

[Arkcon]

I'd like to welcome you, Jacksincy12:, the the Chemical Forums, but I'd like to ask you to read the Forum Rules{click}.  We don't dump complete answers on this forum, we like to help you learn to help yourself.

The equilibrium constant, can you use that, in a formula, to determine how much of the products are there?  Can you use another formula, to relate the concentration of the products to the pH?  You will need this formula for the next step.