Which of the following is least likely to act as a Lewis base?

1.	NH3	2.	BF3
3.	OH-	4.	H2O

The polymer that can be classified as polyster polymer is:
1. Bakelite
2. Melamine
3. Nylon-66
4. Terylene

A buffer solution is prepared in which the concentration of NH₃ is 0.30 M and the concentration of  $N{H}_4^{+\hspace{0.17em}}$ is 0.20 M. If the equilibrium constant, K_b for NH₃ equals 1.8×10^–5, then what is the pH of this solution? 
(log 1.8 = 0.25; log 0.67 = –0.176)

1.  9.43
2.  11.72
3.  8.73
4.  9.08

What is the standard cell potential when the Sn⁴⁺/Sn²⁺ (E° = +0.15 V) and Cr³⁺/Cr (E° = −0.74 V) half-cells are connected under standard conditions?

1. +0.89 V

2. +0.18 V

3. +1.83 V

4. +1.199 V

The product 'D' in the below-mentioned reaction will be:

1.		2.
3.		4.

The correct IUPAC name of the given compound is:

1. 3-Ethyl-4-ethenylheptane

2. 3-Ethyl-4-propylhex-5-ene

3. 3-(1-Ethyl propyl) hex-1-ene

4. 4-Ethyl-3-propylhex-1-ene

The product formed in the below mentioned reaction is:

1.		2.
3.		4.

Calculate the H–H bond dissociation energy from the following reaction:

4H(g) → 2H₂(g)  ΔH = −869.6 kJ

1. -869.6 kJ
2. +434.8kJ
3. +217.4kJ
4. -434.8 kJ