Home
Class 12
CHEMISTRY
Calculate the amount of (NH(4))(2)SO(4) ...

Calculate the amount of `(NH_(4))_(2)SO_(4)` in grams which must be added to `500 ml` of `0.2 M NH_(3)` to yield a solution of `pH=9`, `K_(b)` for `NH_(3)=2xx10^(-5)`

A

3.248g

B

4.248g

C

1.320g

D

6.248g

Text Solution

Verified by Experts

`pOH =-log K_b +log ([NH_(4)^(+)])/([NH_(4)OH])`
Let ‘a’ millimoles of `NH_4^+` are added to a solution having milli moles of `NH_(4)OH=500 xx 0.2=100`
`therefore [NH_(4)^(+)]=["salt"]=a/500`
and `[NH_(4)OH]=["Base"]=100/500`
Given `K_b" for "NH_(4)OH=2 xx 10^(-5) and pH =9`
`therefore 5 =- log 2 xx 10^(-5)+log (a//500)/(100/500)`
`therefore "a=200 mili moles"=0.2"mol moles of"(NH_(4))_(2) SO_(4)` added `=a/2 =0.1 mol`
`therefore W_((NH_(4))_(2)SO_(4))=0.1 xx 132=1.32`
Promotional Banner

Topper's Solved these Questions

  • IONIC EQUILIBRUIM

    MOTION|Exercise Exercise -1|58 Videos
  • IONIC EQUILIBRUIM

    MOTION|Exercise Exercise -2 (Level -1)|37 Videos
  • HYDROCARBON

    MOTION|Exercise Exercise - 4 (Level-II)|15 Videos
  • ISOMERISM

    MOTION|Exercise Exercise 4|26 Videos

Similar Questions

Explore conceptually related problems

Calculate the amount of (NH_(4))_(2)SO_(4) in grams which must be added to 500ml of 0.2MNH_(3) to give a solution of pH=9.3 .Given pK_(b) for NH_(3)=4.7 .

Calculate the weight of (NH_(4))_(2)SO_(4) which must be added to 500mL of 0.2M NH_(3) to yield a solution of pH = 9.35. K_(a) for NH_(3) = 1.78 xx 10^(-5) .

What will be the amount of (NH_(4))_(2)SO_(4) (in g) which must be added to 500 mL of 0.2 M NH_(4)OH to yield a solution of pH 9.35? ["Given," pK_(a)"of "NH_(4)^(+)=9.26,pK_(b)NH_(4)OH=14-pK_(a)(NH_(4)^(+))]

Amount of (NH_(4))_(2)SO_(4) which must be added to 50mL of 0.2 M NH_(4)OH solution to yield a solution of pH 9.26 is ( pK_(b) of NH_(4)OH=4.74 )

Calculate pH of - 10^(-3) NH_(2)SO_(4)