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NEET
Exam
NEET
Subject
Chemistry
Chapter
Redox Reactions

NEET · Chemistry · Redox Reactions

What is the purpose of thiosulfate ions (S 2 O 3 2-) in iodometry?

What is the purpose of thiosulfate ions (S2O32-) in iodometry?

Options

  1. ATo oxidize iodine to iodide ions.
  2. BTo reduce iodine to iodide ions.
  3. CTo form a blue complex with iodine.
  4. DTo stabilize Cu2I2 precipitate.

Correct answer

B. To reduce iodine to iodide ions.

Step-by-step solution

Thiosulfate ions (S2O32-) are used to reduce iodine (I2) back to iodide ions (I⁻) in the reaction, effectively consuming the liberated iodine.
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