00:01
To calculate the ph of a solution of ammonia, we need to consider the equilibrium reaction of ammonia with water, nh3 plus h2o kf nh4 plus plus oh negative.
00:20
The kb value represents the equilibrium constant for the reaction of nh3 with water and is given as 1 .8 into 10 to the power minus 5.
00:29
Since we are given the concentration of nh3 as 0 .34 m, we can assume that it fully dissociates into nh4 plus and oh negative ions.
00:43
Therefore, the concentration of nh4 positive and oh negative ions is also 0 .34 m.
00:51
To find the oh negative concentration, we can use the kb expression.
00:56
Kb is equal to nh4 positive oh negative divided by nh3.
01:11
Since the concentration of nh4 positive and oh negative ions is the same, we can replace them with x in the equation.
01:19
Kb is equal to x square divided by 0 .34 minus x.
01:29
By substituting the value of kb and rearranging the equation, we can solve 1 .8 into 10 to the power minus 5 is equal to x square divided by 0 .34 minus x...