Question

A buffer solution with pH 9 is to be prepared by
mixing NH4Cl and NH OH. Calculate the number of
moles of NH CI that should be added to 1 litre of
1M NH,OH, Kp = 1.8x10-5
(1) 3.6
(2) 1.8
(3) 0.9
(4) 0.225​

Answer 1

Answer:

Its a basic buffer pH=9;pOH=5

pOH=pK

b

+log[

(Base)

(Salt)

]

5=−log(108×10

−5

)+log[

NH

4

OH

NH

4

Cl

]

5=4.745+log[NH

4

Cl]

no. of Moles of NH

4

Cl added=1.8