Calculate pH of the solution obtained by mixi | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(D) The reaction between $NH_4Cl$ and $NaOH$ is: $NH_4Cl + NaOH ightarrow NH_4OH + NaCl$ Initial moles: $n(NH_4Cl) = 0.2 \ M 	imes 0.050 \ L = 10 \

Vedclass · Accepted Answer

$9.74$

Vedclass · Answer

(D) The reaction between $NH_4Cl$ and $NaOH$ is: $NH_4Cl + NaOH ightarrow NH_4OH + NaCl$ Initial moles: $n(NH_4Cl) = 0.2 \ M 	imes 0.050 \ L = 10 \ mmol$ $n(NaOH) = 0.1 \ M 	imes 0.075 \ L = 7.5 \ mmol$ After reaction: $n(NH_4Cl) = 10 - 7.5 = 2.5 \ mmol$ $n(NH_4OH) = 7.5 \ mmol$ This forms a basic buffer solution containing a weak base $(NH_4OH)$ and its salt $(NH_4Cl)$. Using the Henderson-Hasselbalch equation for a basic buffer: $pOH = pK_b + \log \frac{[Salt]}{[Base]}$ $pOH = 4.74 + \log \frac{2.5}{7.5} = 4.74 + \log \frac{1}{3}$ $pOH = 4.74 - 0.477 = 4.263$ Now,calculate $pH$: $pH = 14 - pOH = 14 - 4.263 = 9.737 \approx 9.74$

Buffer Solution	Volume of $0.1 \ M$ Weak Acid (mL)	Volume of $0.1 \ M$ Sodium Salt (mL)
$I$	$4.0$	$4.0$
$II$	$4.0$	$40.0$
$III$	$40.0$	$4.0$
$IV$	$0.1$	$10.0$

Calculate $pH$ of the solution obtained by mixing $50 \ mL$ of $0.2 \ M$ $NH_4Cl$ solution and $75 \ mL$ of $0.1 \ M$ $NaOH$ solution. Given $pK_b$ for aqueous $NH_3$ is $4.74$.

Similar Questions

$pH$ of a mixture of $1 \ M$ benzoic acid $(pK_a = 4.20)$ and $1 \ M$ $C_6H_5COONa$ is $4.5$. What is the volume of benzoic acid required to prepare a $300 \ mL$ buffer solution (in $mL$)? $[\log 2 = 0.3]$

Buffer Solution Volume of $0.1 \ M$ Weak Acid (mL) Volume of $0.1 \ M$ Sodium Salt (mL)

$I$ $4.0$ $4.0$

$II$ $4.0$ $40.0$

$III$ $40.0$ $4.0$

$IV$ $0.1$ $10.0$

Which of the two sets of buffer solutions have the least $pH$?

$A$ buffer solution can be prepared from a mixture of

The $pH$ of blood is

Which buffer is present in human blood :-

Vedclass Test Series

Exam Paper Generator

Online Exam Module