How many grams of dry nh4cl need to be added to 1.90 l of a 0.500 m solution of ammonia, nh3, to prepare a buffer solution that has a ph of 8.72? kb for ammonia is 1.8×10−5.

Answer : The mass of dry needed are, 174.196 grams.

Explanation :

First we have to calculate the pOH of the solution.

Now we have to calculate the .

Now we have to calculate the concentration of base, .

Using Henderson Hesselbach equation :

Now put all the given values in this equation, we get :

Now we have to calculate the mass of .

Formula used :

Now put all the given values in this formula, we get:

Therefore, the mass of dry needed are, 174.196 grams.

the answer is c

tell me if wrong