The most stable carbocation among the following is:

1.		2.
3.		4.

The compound which forms one monochloro product when treated with chlorine is:

(1) n-pentane

(2) isopentane

(3) neo-pentane

(4) None of these

Among the following anions (a) CH₃, (b) NH₂, (c) OH^-, (d) F^-, the order of basicity is:

1. a > b > c > d

2. b > a > c > d

3. c > b > a > d

4. c > a > b > d

The electromeric effect in organic compounds is a

1. Temporary effect

2. Permanent effect

3. Electromeric effect is only observed in inorganic molecules

4. None of the above

The arrangement in decreasing order of stability of $\stackrel{\bullet }{C}$H₃, $\stackrel{\bullet }{C_2}$H₅,(CH₃)₂$\stackrel{\bullet }{C}$H and (CH₃)₃ $\stackrel{\bullet }{C}$ free radicals is-

1. $\stackrel{\bullet }{C}$H₃ > $\stackrel{\bullet }{C_2}$H₅ > (CH₃)₂$\stackrel{\bullet }{C}$H > (CH₃)₃ $\stackrel{\bullet }{C}$  

2. (CH₃)₃ $\stackrel{\bullet }{C}$ > (CH₃)₂$\stackrel{\bullet }{C}$H > $\stackrel{\bullet }{C_2}$H₅ > $\stackrel{\bullet }{C}$H₃

3. $\stackrel{\bullet }{C_2}$H₅ > $\stackrel{\bullet }{C}$H₃ > (CH₃)₂$\stackrel{\bullet }{C}$H > (CH₃)₃ $\stackrel{\bullet }{C}$

4. (CH₃)₃ $\stackrel{\bullet }{C}$ > (CH₃)₂$\stackrel{\bullet }{C}$H >  $\stackrel{\bullet }{C}$H₃  >$\stackrel{\bullet }{{\mathrm{ C}}_2}$H₅ 

The species that contains only three pairs of electrons among the following is-

H₂C = O behaves as:

1. Nucleophile

2. Electrophile

3. Both (1) and (2)

4. None of the above 

Electrophiles are:

1. electron loving species            

2. electron hating species

3. nucleus loving reagents            

4. nucleus hating reagents

Nucleophiles are:

1. electron loving

2. electron hating

3. nucleus loving

4. nucleus hating

The sigma bond energy of C-H bond in C₂H₆ is:

(1) 99 kcal

(2) 140 kcal

(3) 200 kcal

(4) 60 kcal