Calculate the concentration of aqueous solution of barium hydroxide whose pH is 12
Ba(OH)2 ==> Ba^2+ + 2OH^-
Convert pH to OH^-, take half of it and that is the M concn of Ba(OH)2.
Dr Bob thanks but am not clear on the half.am i supposed 2to half of the pOH or the concentration?
Don't take 1/2 pH. Convert pH to OH^-, take 1/2 the OH. Look at the equation I wrote--1 Ba(OH)2 = 2 OH so taking 1/2 the OH will give you the Ba(OH)2 and concn Ba(OH)2 is what you want.
Thanks i get it now
To calculate the concentration of an aqueous solution of a compound, including barium hydroxide (Ba(OH)2), based on its pH, you need to use the concept of pOH, which is the negative logarithm of the hydroxide ion concentration in a solution.
1. Find the pOH value: To calculate the pOH, subtract the pH from 14, since pH + pOH = 14. In this case, pOH = 14 - 12 = 2.
2. Find the hydroxide ion concentration: To calculate the hydroxide ion concentration, you need to convert the pOH value into a numerical value using the equation: pOH = -log[OH-]. Rearranging the equation, you get [OH-] = 10^(-pOH). In this case, [OH-] = 10^(-2) = 0.01 M.
3. Determine the concentration of barium hydroxide: Since barium hydroxide (Ba(OH)2) dissociates in water to form two hydroxide ions for every molecule of Ba(OH)2, the concentration of Ba(OH)2 will be half of the hydroxide ion concentration. Therefore, the concentration of Ba(OH)2 is 0.01 M / 2 = 0.005 M.
So, the concentration of the aqueous solution of barium hydroxide with a pH of 12 is 0.005 M.