(A) For a basic buffer,the formula is $pOH = pK_b + \log \left( \frac{[Salt]}{[Base]} \right)$.Given: $[Salt] = [NH_4^+] = 0.20 \ M$,$[Base] = [NH_3]

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(A) For a basic buffer,the formula is $pOH = pK_b + \log \left( \frac{[Salt]}{[Base]} \right)$.Given: $[Salt] = [NH_4^+] = 0.20 \ M$,$[Base] = [NH_3] = 0.30 \ M$,and $K_b = 1.8 \times 10^{-5}$.First,calculate $pK_b = -\log(K_b) = -\log(1.8 \times 10^{-5}) \approx 4.74$.Now,$pOH = 4.74 + \log \left( \frac{0.20}{0.30} \right) = 4.74 + \log(0.667) = 4.74 - 0.176 = 4.564$.Finally,$pH = 14 - pOH = 14 - 4.564 = 9.436 \approx 9.43$.

Class 11 Chemistry 6-2.Equilibrium-II (Ionic Equilibrium)Buffer solution

Medium

$A$ buffer solution is prepared with a concentration of $0.30 \ M \ NH_3$ and $0.20 \ M \ NH_4^+$. If the equilibrium constant for $NH_3$ is $K_b = 1.8 \times 10^{-5}$,what will be the $pH$ of this solution?

A
$9.43$
B
$4.57$
C
$9.26$
D
$4.74$

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6-2.Equilibrium-II (Ionic Equilibrium)

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Buffer solution

$20 \ mL$ of $0.1 \ M \ H_2SO_4$ is added to $30 \ mL$ of $0.2 \ M \ NH_4OH$ solution. The $pH$ of the resultant mixture is [$pK_b$ of $NH_4OH = 4.7$].

DifficultJEE MAIN 2019

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$2 \ g$ acetic acid and $3 \ g$ sodium acetate are present in $100 \ mL$ aqueous solution. What will be the $pH$ of the solution if the ionisation constant of acetic acid is $1.8 \times 10^{-5}$?

Medium

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The $pK_a$ of a weak acid is $4.8$. What should be the ratio of $\frac{[\text{acid}]}{[\text{salt}]}$, if a buffer of $pH = 5.8$ is required?

MediumTS EAMCET 2001

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$A$ buffer solution of $100 \ mL$ has a $pH$ value of $4$. When $1 \ mL$ of dilute $HCl$ is added to it,what happens to the $pH$ of the buffer solution?

Easy

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Which of the following is a buffer solution?

Medium

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$A$ buffer solution is prepared with a concentration of $0.30 \ M \ NH_3$ and $0.20 \ M \ NH_4^+$. If the equilibrium constant for $NH_3$ is $K_b = 1.8 \times 10^{-5}$,what will be the $pH$ of this solution?

Similar Questions

$20 \ mL$ of $0.1 \ M \ H_2SO_4$ is added to $30 \ mL$ of $0.2 \ M \ NH_4OH$ solution. The $pH$ of the resultant mixture is [$pK_b$ of $NH_4OH = 4.7$].

$2 \ g$ acetic acid and $3 \ g$ sodium acetate are present in $100 \ mL$ aqueous solution. What will be the $pH$ of the solution if the ionisation constant of acetic acid is $1.8 \times 10^{-5}$?

The $pK_a$ of a weak acid is $4.8$. What should be the ratio of $\frac{[\text{acid}]}{[\text{salt}]}$, if a buffer of $pH = 5.8$ is required?

$A$ buffer solution of $100 \ mL$ has a $pH$ value of $4$. When $1 \ mL$ of dilute $HCl$ is added to it,what happens to the $pH$ of the buffer solution?

Which of the following is a buffer solution?

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