SELECT * FROM question_mgmt as q WHERE id=1893 AND status=1 SELECT id,question_no,question,chapter FROM question_mgmt as q WHERE courseId=3 AND subId=9 AND chapterId=61 and ex_no='2' AND status=1 ORDER BY CAST(question_no AS UNSIGNED)

Question:

Name the processes from which chlorine is obtained as a by-product. What will happen if an aqueous solution of NaCl is subjected to electrolysis?

Answer:

In the electrolysis of molten NaCl, Cl2 is obtained at the anode as a by product.

NaCl(melt)   →  Na+(melt)  + Cl-(melt)

 

At cathode:  Na+(melt)   + e-    →   Na(s)

At anode: Cl-(melt)    →  Cl(g) + e-

2Cl(g)  →  Cl2(g)

The overall reaction is as follows:

If an aqueous solution of NaCl is electrolyzed, Cl2 will be obtained at the anode but at the cathode, H2 will be obtained (instead of Na). This is because the standard reduction potential of Na (E°= - 2.71 V) is more negative than that of H2O (E° = - 0.83 V). Hence, H2O will get preference to get reduced at the cathode and as a result, H2 is evolved.

NaCl(aq)  →  Na+(aq) + Cl-(aq)

At cathode:  2 H2O(l)  +  2e-   →   H2(g) + 2OH-(aq)   

At anode: Cl-(melt)    →  Cl(g) + e-

2Cl(g)  →  Cl2(g)


SELECT ex_no,question,question_no,id,chapter FROM question_mgmt as q WHERE courseId='3' AND subId='9' AND ex_no!=0 AND status=1 and id!=1893 ORDER BY views desc, last_viewed_on desc limit 0,10
SELECT ex_no,question,question_no,id,chapter FROM question_mgmt as q WHERE courseId='3' AND subId='9' AND ex_no!=0 AND status=1 and id!=1893 ORDER BY last_viewed_on desc limit 0,10

Comments

  • Answered by Ekta Mehta
  • 4 months ago

Taking Screenshots on your Samsung Galaxy M31s is very easy and quick.


  • Answered by Ekta Mehta
  • 4 months ago

Taking Screenshots on your Samsung Galaxy M31s is very easy and quick.


  • Answered by Ekta Mehta
  • 4 months ago

Taking Screenshots on your Samsung Galaxy M31s is very easy and quick.


Comment(s) on this Question