AP EAMCET · Chemistry · s Block Elements

Potassium cyanide is made alkaline with $NaOH$ and boiled with thiosulphate ions. The solution is cooled and acidified with $HCl$ and this solution with iron $(III)$ chloride produces :-

A Prussian blue colour solution
B Blood red colour solution
C Dark brown colour solution
D Green colour solution

Verified Solution

Answer & Solution

Correct Answer

(B) Blood red colour solution

Step-by-step Solution

Detailed explanation

The reaction of potassium cyanide with sodium hydroxide gives the cyanide ion. After that cyanide ion reacts with the thiosulphate ions and cool and acidify in presence of the hydrochloric acid. It gives the thiocyanide ion. KCN + NaOH→NaCN + KOH…

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.

Same subject

	List-I		List-II
A)	112	I)	s
B)	116	II)	p
C)	88	III)	d
D)	100	IV)	f

Explore more questions on app

From AP EAMCET

Explore more questions on app

	List-I		List-II
	(Atomic number, Z)		(Block)
A)	112	I)	s
B)	116	II)	p
C)	88	III)	d
D)	100	IV)	f

Potassium cyanide is made alkaline with NaOH and boiled with thiosulphate ions. The solution is cooled and acidified with HCl and this solution with iron (III)chloride produces :-

Step-by-step Solution

Potassium cyanide is made alkaline with $NaOH$ and boiled with thiosulphate ions. The solution is cooled and acidified with $HCl$ and this solution with iron $(III)$ chloride produces :-