Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert

The K sp of FeS=4× 10 19 at 298K. The minimum concentration of H + ions required to prevent the precipitation of FeS from a 0.01M solution Fe 2+ salt by passing  H 2 S

(Given  H 2 S k a 1 × k b 1 = 10 21 )
ChemistryIonic EquilibriumJEE Main
Options:
  • A 1.6 × 103 M
  • B 2.5 × 104 M
  • C 2.0 × 102 M
  • D 1.2 × 104 M
Solution:
2600 Upvotes Verified Answer
The correct answer is: 1.6 × 103 M
Fe2+ S2=4 × 1019 S2=4×10191×102= 4×1017 M

In order to precipitate FeS, S2 required is 4 × 1017 M from 0.01 M Fe2+ salts.

Now H+24×10170.1= 1 × 1021

 H+2 =2.5 × 106

 H+=1.6 × 103

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.