When `t`-butanol and `n`-butanol are separately treated with a few drops of dilute `KMnO_(4)` in one case only, the purple colour disappears and brown precipitate is formed. Which of the two alcohols gives the above reaction and which is the brown precipitate?

When a crystalline compound X is heated with K_(2)Cr_(2)O_(7) and concentrated H_(2)SO_(4) , a reddish brown gas A is evolved. On passing A into caustic soda, a yellow solution of B is formed. A yellow precipitate of C is obtained when a solution B is neutralised with acetic acid and then treated with a lead acetate solution. when X is heated with NaOH , a colourless gas is evolved which, when passed into a solution of K_(2)[HgI_(4)] , gives a reddish brown precipitate of D. ltBrgt Q. Which of the following is the composition of the brown precipitate (D) ?

Gradual addition of KI solution to Bi(NO_3)_(3) solution initially produces a dark brown precipitate which dissolves in excess of KI to give a clear yellow solution. Write chemical equation for the above reactions.

Gradual addition of KI solution to Bi(NO_3)_(3) solution initially produces a dark brown precipitate which dissolves in excess of KI to give a clear yellow solution. Write chemical equation for the above reactions.

An aqueous solution of a white salt A gives a white precipitate B on treatment with dilute HCl in cold condition. B is soluble in boiling water. An aqeous solution of A gives a yellow precipitate on treatment with a solution of K_(2)CrO_(4) . The soda extract of A is acidified with diolute H_(2)SO_(4) , boiled to remove CO_(2) and treated with a freshly prepared solution of FeSO_(4) . concentratd H_(2)SO_(4) is added to the resulting solution. a brownn ring is formed at the junction of the two layers. Q. A solution of A, when treated with NH_(3) , gives:

A chemist opened a cupboard and found four bottles containing water solutions, each of which had lost its label.Bottles 1,2,3 contanied colourless solution, while bottle 4 contained a blue solution.The labels from the bottles were lying scattered on the floor of the cupboard.They were: copper (II) sulphate, Hydrochloric acid lead nitrate , Sodium carbonate By mixing samples of the contents of the bottles, in pairs , the chemist made the following observations : Bottle 1 +Bottle 2 to White precipitate is formed. Bottle 1 +Bottle 3 to White precipitate is formed. Bottle 1 +Bottle 4 to White precipitate is formed. Bottle 2 +Bottle 3 to Colourless and odourless gas is evolved. Bottle 2 +Bottle 4 to No visible reaction is observed. Bottle 3 +Bottle 4 to Blue precipitate is formed. With the help of the above observations answer the following questions. Which one of the following bottles develops deep blue with aqueous ammonia ?

Identify the cations in each of the following cases : (i) NaOH solution when added to the Solution (A) gives a reddish brown precipitate. (ii) NH4OH Solution when added to the Solution (B) gives white precipitate which does not dissolve in excess.

p-Amino-N,N-dimethylaniline is added to a strongly acidic solution of X. The resulting solution is treated with a few drops of aqueous solution of Y to yield blue colouration due to the formation of methylene blue. Treatment of aqueous solution of Y with reagent potassium hexacyanoferrate (II) leads to the formation of an intense blue precipitate. The precipitate dissolves on excess addition of the reagent. Similarly, the treatment of the solution of Y with the solution of potassium hexacyanoferrate (III) leads to a brown colouration due to the formation of Z. Q. Compound X is

p-Amino-N,N-dimethylaniline is added to a strongly acidic solution of X. The resulting solution is treated with a few drops of aqueous solution of Y to yield blue colouration due to the formation of methylene blue. Treatment of aqueous solution of Y with reagent potassium hexacyanoferrate (II) leads to the formation of an intense blue precipitate. The precipitate dissolves on excess addition of the reagent. Similarly, the treatment of the solution of Y with the solution of potassium hexacyanoferrate (III) leads to a brown colouration due to the formation of Z. Q. Compound Y is

p-Amino-N,N-dimethylaniline is added to a strongly acidic solution of X. The resulting solution is treated with a few drops of aqueous solution of Y to yield blue colouration due to the formation of methylene blue. Treatment of aqueous solution of Y with reagent potassium hexacyanoferrate (II) leads to the formation of an intense blue precipitate. The precipitate dissolves on excess addition of the reagent. Similarly, the treatment of the solution of Y with the solution of potassium hexacyanoferrate (III) leads to a brown colouration due to the formation of Z. Q. Compound Z is

A white solid P, on strong heating, decomposes to give reddish brown gas R and a residue Q. The residue Q is yellow when hot and white when cold. The solution of white solid P in water gives white precipitate S, with concentrated sodium hydroxide. The white precipitate S dissolves in excess of sodium hydroxide solution to form colourless solution. Another sample of the solid P in water is mixed with ferrous sulphate solution and then to this solution are added a few drops of conc. sulphuric acid. A brown ring is formed at the junction of liquids. Answer the following questions: Name the white precipitate S.