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Multiple choice chemistry amines chemical reactions of diazonium salts chemical properties of diazonium salts diazonium salts

3- Amino-2, 3-dimethyl butan-2-ol when treated with $ NaNO _{2}/HCl$ gives product (X). (X) on treatment with $LiAlH _{4}$ forms (Y). (Y) on heating with $conc. H _{2}SO _{4}$ forms (Z). The molecular weight of (Z) is :

  1. 81

  2. 82

  3. 83

  4. 84
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

3- Amino-2, 3-dimethyl butan-2-ol is diazotized with sodium nitrite in presence of HCl at low temperature to obtain 3,3-dimethylbutan-2-one (compound X).
The carbonyl group is then reduced to obtain 3,3-dimethylbutan-2-ol (compound Y). This is followed by dehydration to obtain 2,3-dimethylbut-2-ene (compound Z).

Multiple choice chemistry organic compounds containing nitrogen chemical reactions of diazonium salts chemical properties of diazonium salts diazonium salts

Cyanide group on hydrolysis give:

  1. acid

  2. acetamide

  3. amine

  4. hydrate
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
$\displaystyle \underset{Cyanide}{RCN} \xrightarrow{H _2O} \underset{Amide}{RCONH _2}   \xrightarrow{H _2O} \underset{Acid}{RCOOH} + \underset{Ammonia}{NH _3}$
$\therefore $ Hydrolysis of cyanide results in formation of acid.
Multiple choice chemistry organic compounds containing nitrogen chemical reactions of diazonium salts chemical properties of diazonium salts diazonium salts

The reagent commonly used to determine hardness of water titrimetrically is:

  1. Oxalic acid

  2. Disodium salt of EDTA

  3. Sodium citrate

  4. Sodium thiosulphate

  5. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The total hardness of water (i.e. the concentration of dissolved cations such as $Ca^{2+}, Mg^{2+}, Fe^{3+}$ etc.) is commonly determined by the titration of a water sample with a standardized solution of the disodium salt of ethylenediaminetetraacetic acid (EDTA) using eriochrome black T or calmagite as an indicator. Calmagite has the advantage of forming indefinitely stable solutions and will be substituted without any other modification to the procedure.
Hence option B is correct.

Multiple choice chemistry organic compounds containing nitrogen chemical reactions of diazonium salts chemical properties of diazonium salts diazonium salts

Shweta found her pet's cloth discoloured and decided to renovate the dress by colouring it. Which of the following solution of compound should she choose to do so?

  1. Ammonia

  2. Ester

  3. Diazonium salts

  4. Aldehyde
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Diazonium salts are used for making azo dye at lone temperature by coupling with $\beta$-naphthol or any other alcohol. and is used for dyeing clothes.

Multiple choice chemistry organic compounds containing nitrogen chemical reactions of diazonium salts chemical properties of diazonium salts diazonium salts

When diazonium salt solution is treated with water at a temperature of 283 K it forms:

  1. ester

  2. alcohol

  3. amines

  4. phenol
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

When an aqueous solution of an aromatic diazonium salt is warmed (often at temperatures around 283-300 K), it undergoes hydrolysis to form phenol and nitrogen gas.

Multiple choice chemistry organic compounds containing nitrogen chemical reactions of diazonium salts chemical properties of diazonium salts diazonium salts

Which of the following is correct method to convert p-toluidine to p-toluic acid?

  1. $ Diazotisation, \, CuCN, \, H _2/Pd$
  2. $CHCl _3/NaOH,\, KCN, \, Sn/HCl$
  3. $ Diazotisation, \, CuCN/KCN, H _2O/H^+$
  4. $ Diazotisation, \, NaCN, \, NaOH$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

To convert p-toluidine to p-toluic acid, one must diazotize the amine, replace the diazonium group with a cyano group using CuCN, and then hydrolyze the nitrile to a carboxylic acid.

Multiple choice chemistry nuclear physics hazards and safety measures of radiations harmful effects and safety precautions for radiations energy production

Fill in the blank.
__________ arises from the 'burning' of uranium fuel in a nuclear reactor. 

  1. Low-level- waste

  2. High-level waste

  3. Intermediate level waste

  4. Very low level waste
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

High level waste 

High level radioactive waste are highly radioactive materials produced as a by product of the nuclear reactions that occurs inside the nuclear reactor.