Chemistry - Salt Analysis Question with Solution | TestHub
Select CORRECT statement(s).
Options:(select one or more)
Answer:
Solution:
Question Explanation:
Identify the chemically correct statements from the provided list concerning phosphorus, thiocyanate, helium, and thiosulphate.
Concept:
P-block chemistry, Qualitative Analysis, and Redox Titrations.
Solution:
Statement 1 (Correct): White phosphorus (P4 ) undergoes disproportionation in boiling concentrated alkali (NaOH) to produce phosphine (PH₃) and sodium hypophosphite.
Statement 2 (Correct): Thiocyanate (SCN⁻) is a pseudohalide (mimics halide properties). It reacts with ferric ions (Fe³⁺) to form a blood-red complex, .
Statement 3 (Correct): Helium is mixed with oxygen (Heliox) for scuba diving tanks because its low solubility in blood prevents nitrogen narcosis and decompression sickness ("the bends").
Statement 4 (Correct): Standardized Hypo (Sodium Thiosulfate, Na₂S₂O₃) solution is the specific reagent used to titrate against iodine (I₂) in iodometric analysis.
The reaction is:
(Tetrathionate)
Final Answer: Option (A), (B ), (C) and (D)