VKC ScienceChemistry for written exams Telegram

UPSC Combined Geo-Scientist

Chemist

  • 2 objective papers
  • 120 questions each
  • 2 h per paper
  • 100 + 300 marks

Prelims Paper II covers chemistry.

UPSC Combined Geo-Scientist, Prelims · 2020 · Paper II, Chemistry · Q79 of 120

Geo-Scientist Prelims 2020 Chemistry Q79: When HCl is titrated against NaOH, the conductance at the end point…

QuestionElectrochemistry / conductometric titration

When HCl is titrated against NaOH, the conductance at the end point is:

  1. (a) Zero
  2. (b) Minimum
  3. (c) Maximum
  4. (d) Infinite

Answer: (b) Minimum

Fast H⁺ (λ° ≈ 350) is replaced by slow Na⁺ (≈ 50): conductance falls to the end point, then rises as excess OH⁻ (≈ 198) is added. V-shaped curve → minimum at the end point → (b).

Take this paper offlineAll 120 questions with answers and explanations in one PDF.
Download PDFJoin Telegram