To an aqueous solution containing anions a few drops of acidified KMnO₄ are added. Which one of the following anions, if present will not decolourise the KMnO₄ solution ?

• I^-

• CO${}_3^{2-}$

• S^2-

• NO${}_2^{-}$

In the following reaction,

M^x+ + MnO${}_4^{-}$ → MO${}_3^{-}$ + Mn²⁺ + $\frac{1}{2}$O₂

If one mole of MnO${}_4^{-}$ oxidises 2.5 moles of M^x+, then the value of x is

• 5

• 3

• 2

• 1

0.25 g of an organic compound on Kjeldahl's analysis gave enough ammonia to just neutralize 10 cm³ of 0.5 M H₂SO₄. The percentage of nitrogen in the compound is

• 28

• 56

• 14

• 112

Lassaigne's test for the detection of nitrogen fails in

• H₂N-CO-NHNH₂.HCl

• NH₂-NH₂.HCl

• NH₂-CO-NH₂

• C₆H₅-NH-NH₂.HCl

25.

When tetrahydrafuran is treated with excess HI, the product formed is

• 1, 4-diiodobutane

• 1,4-butanediol

• 2-iodotetrahydrofuran

• 4-iodo-1-butanol

Pick out the correct statements from the following and choose the correct answer from the codes given below

1. Hexa-1, 5-diene is a conjugated diene
2. Prop-1, 2-diene is conjugated diene
3. Hexa-1, 3-diene is a conjugated diene
4. Buta-1, 3-diene is an isolated diene
5. Prop-1, 2-diene is a cumulative diene

• 1, 2

• 3, 5

• 2, 3

• 4, 5

Select R-isomers from the following

• I and III

• II, IV and V

• I, II and III

• II and III

The correct IUPAC name of the acid

• Z-3-ethyl-4methyl hex-3-en-1-oic acid

• E-3-ethyl-4-ethylhex-3-en-1-oic acid

• Z-3-ethyl-4-methyl hexanoic acid

• Z-3, 4-diethylpent-3-en-1-oic acid

(CH₃)₃CMgCl on reaction with D₂O produces

• (CH₃)₃COD

• (CD₃)₃CH

• (CH₃)₃CD

• (CD₃)₃CD

The elements present in the core of earth are collectively known as

• lithophiles

• nucleophiles

• chalcophiles

• siderophiles