Go To Your Study Dashboard

Get Answers to all your Questions

header-bg

$\mathrm{2.5 \mathrm{~g}}$ of $\mathrm{Al}$ metal was treated with $\mathrm{85 \mathrm{~mL}}$ of $\mathrm{\mathrm{H}_2 \mathrm{SO}_4}$ having specific gravity of 1.18 . After complete dissolution of the metal, the resultant solution was diluted to $\mathrm{500 \mathrm{~mL}}$ . Find the molarity of free $\mathrm{\mathrm{H}_2 \mathrm{SO}_4 }$ in the final solution if $\mathrm{24.7 \% \, \, \, \mathrm{H}_2 \mathrm{SO}_4}$ by weight was used.
Option: 1
0.1825 M

Option: 2
0.228 M

Option: 3
0.689 M

Option: 4
1.031 M

Answers (1)

best_answer

Molarity of $\mathrm{\mathrm{H}_2 \mathrm{SO}_4 \, \, }$ solulion taken $=$

$\mathrm{=\frac{24.7 \times 1000}{98 \times 100} \times 1.18=2.974 \mathrm{M}}$

$\mathrm{\text { Moles of } Al \text { taken }=\frac{2.5}{27}=0.092}$

$\mathrm{\text { Moles of } \mathrm{H}_2 \mathrm{SO}_4 \text { taken }=\frac{85 \times 2.974}{1000}}$

$\mathrm{=0.252}$

$\mathrm{\underset{2\ moles}{2 \mathrm{Al}}+\underset{3\ moles}{3 \mathrm{H}_2 \mathrm{SO}_4 }\rightarrow \mathrm{Al}_2\left(\mathrm{SO}_4\right)_3+3 \mathrm{H}_2}$

$\mathrm{0.092 \, \, moles \quad 0.092 \times \frac{3}{2}=0.138 \, \, moles}$

$\therefore$ $\mathrm{A l}$ is the limiting regent.

Hence, mols of $\mathrm{ \mathrm{H}_2 \mathrm{SO}_4}$ remaining $\mathrm{ =0.252-0.138}$

$\mathrm{ =0.114 \text { moles }}$

Now volume of solution is made to be $\mathrm{500 \mathrm{~mL}}$

Hence $\mathrm{M}$ of free $\mathrm{ \mathrm{H}_2 \mathrm{SO}_4}$ in the resulting solution

$\mathrm{ \begin{aligned} & =\frac{0.114}{500} \times 1000 \\ & =0.228 \mathrm{M} \end{aligned} }$

Posted by

sudhir kumar

View full answer

JEE Main high-scoring chapters and topics

Study 40% syllabus and score up to 100% marks in JEE

Similar Questions

50 mL of 0.2 M ammonia solution is treated with 25 mL of 0.2 M HCl. If pK_b of ammonia solution is 4.75, the pH of the mixture will be :
Option: 1 3.75
Option: 2 4.75

Trending Articles/News

anam-khan

JEE Main 2026 application correction begins on jeemain.nta.nic.in; edit details by December 2

anam-khan

JEE Mains 2026 LIVE: NTA to conduct session 1 from January 21 to 30; exam pattern, syllabus

anam-khan

JEE Main 2026 correction window opens tomorrow; NTA allows exam city change

Latest Question