The enolic form of ethyl acetoacetate is given below-

 

The number of σ and π bonds in the enolic form are respectively:

1. 18 sigma bonds and 2 pi-bonds
2. 16 sigma bonds and 1 pi-bond
3. 9 sigma bonds and 2 pi-bonds
4. 9 sigma bonds and 1 pi-bond

Which structure corresponds to the IUPAC name 3-Ethyl-2-hydroxy-4-methylhex-3-en-5-ynoic acid?

1.		2.
3.		4.

The correct order of increasing bond length of  C-H, C-O, C-C and C=C is:

1.  $\mathrm{C}-\mathrm{C}<\mathrm{C}=\mathrm{C}<\mathrm{C}-\mathrm{O}<\mathrm{C}-\mathrm{H}$

2.  $\mathrm{C}-\mathrm{O}<\mathrm{C}-\mathrm{H}<\mathrm{C}-\mathrm{C}<\mathrm{C}=\mathrm{C}$

3.  $\mathrm{C}-\mathrm{H}<\mathrm{C}-\mathrm{O}<\mathrm{C}-\mathrm{C}<\mathrm{C}=\mathrm{C}$

4.  $\mathrm{C}-\mathrm{H}<\mathrm{C}=\mathrm{C}<\mathrm{C}-\mathrm{O}<\mathrm{C}-\mathrm{C}$

The most reactive compound towards electrophilic reagent among the following is:

1.		2.
3.		4.

The most stable conformation of n-butane among the following is:

1.		2.
3.		4.

The following compounds are given for reference
(1) CH₃-CH₂^–
(2) H₂C=CH^–
(3) HC≡C^– 

The increasing order of basic strength is:
1. (2)>(1)>(3)
2. (3) >(2) >(1)
3. (1) >(3) >(2)
4. (1) >(2)>(3)

How many stereoisomers does this molecule have? 

The stability of carbanions in the following:
 
is in the order of: