ph and POH

[Willow18]

Whatt is the pH and pOH of each solution given the following value of (OH-)? Which solutions are acidic, basic  and neutral?

.  10-3 M    b. 10-1 M    c. 10-5 M   d. 10-7 M   ?


What is the molarity of a solution made by dissolving 3.4 g of ba(OH) in enough water to make 450 mL of solution?
Assume that Ba(OH)2 ionizes completely in water to Ba2+ and OH- ions. What is the pH of the solution?

[kingchemist]

If [OH-] = 10-2 moles/L then pOH = - log[10-2] = 2.
pH = 14 - pOH
pH = 12

Moles Ba(OH)2 = mass of Ba(OH)2/molar mass of Ba(OH)2

Molarity = moles/volume in L

However each Ba(O)2 has 2 x OH- ions per formula. So if [BaOH)2] = 0.5M then [OH-] = 1.0M