During steam distillation, an organic compound vaporizes when the total vapor pressure of the immiscible mixture (organic compound + water) equals the ambient pressure. This process causes the organic compound to vaporize at a temperature that is:

1. The same as its normal boiling point.

2. Lower than its normal boiling point.

3. Higher than its normal boiling point.

4. Independent of its normal boiling point.

Subtopic:  Purification of Organic Compounds |
 73%
Level 2: 60%+
Hints

An organic compound contains 69% carbon, and 4.8% hydrogen, the remainder being oxygen. The masses of carbon dioxide, and water produced when 0.20 g of this substance is subjected to complete combustion would be respectively -

1. 0.506 g, 0.0864 g

2. 0.906 g, 0.0864 g

3. 0.0506 g, 0.864 g

4. 0.0864 g, 0.506 g

Subtopic:  Quantitative Analysis of Organic Compounds |
 63%
Level 2: 60%+
Hints

A sample of 0.50 g of an organic compound was treated according to Kjeldahl’s method. The ammonia evolved was absorbed in 50 mL of 0.5 M H2SO4. The residual acid required 60 mL of 0.5 M solution of NaOH for neutralization. The percentage composition of nitrogen in the compound is:

1. 52% 2. 61%
3. 56 % 4. 54 %
Subtopic:  Quantitative Analysis of Organic Compounds |
 70%
Level 2: 60%+
Hints

advertisementadvertisement

In the organic compound
CH2=CHCH2CH2CCH, which pair of hybridized orbitals is involved in forming the C2–C3 bond?
1. sp – sp2 

2. sp – sp3

3. sp2 – sp3

4. sp3 – sp3

Subtopic:  Hybridisation & Structure of Carbon Compounds |
 83%
Level 1: 80%+
Hints

The correct statement regarding ambident nucleophiles is:

1. Nucleophiles have equal atomic weight.

2. Nucleophiles have only five electrons.

3. Nucleophiles have two nucleophilic sites.

4. Nucleophiles have two electrophilic sites.

Subtopic:  Nucleophile & Electrophile |
 88%
Level 1: 80%+
Hints

Any type of chromatography shares which of the following characteristic?

1. Use of molecules that are soluble in water.

2. Use of inert carrier gas.

3. Calculation of Rf value for the molecule separated.

4. Use of a mobile and a stationary phase.

Subtopic:  Quantitative Analysis of Organic Compounds |
 67%
Level 2: 60%+
Hints

advertisementadvertisement

The number of σ and π bonds in the molecule C6H6 are -

1. 6 C – C sigma ( σ C - C )  bonds, 5 C–H sigma ( ( σ C - H )  bonds, and 3 C=C pi ( π C - C ) 
2. 6 C – C sigma ( σ C - C )  bonds, 5 C–H sigma ( ( σ C - H )  bonds, and 2 C=C pi ( π C - C ) 
3. 6 C – C sigma ( σ C - C )  bonds, 6 C–H sigma ( ( σ C - H )  bonds, and 3 C=C pi ( π C - C ) 
4. 6 C – C sigma ( σ C - C )  bonds, 6 C–H sigma ( ( σ C - H )  bonds, and 2 C=C pi ( π C - C ) 

Subtopic:  Hybridisation & Structure of Carbon Compounds |
 88%
Level 1: 80%+
Hints
Links

The number of σ and π bonds in the molecule C6H12 are:

1. 7 = (σC-C) , 11 =  (σC-H), and 0= π 

2. 6 = (σC-C) , 12 =  (σC-H), and 0= π 

3. 12 = (σC-C) , 6 =  (σC-H), and 1= π 

4. 5 = (σC-C) , 13 =  (σC-H), and 1= π 

Subtopic:  Hybridisation & Structure of Carbon Compounds |
 65%
Level 2: 60%+
Hints
Links

Indicate the σ and π bonds in this molecule CH2=C=CH2

1. two C–C sigma (σC-C) bonds, two C–H sigma (σC-H) bonds, and one C=C pi πC-C bonds

2. four C–C sigma (σC-C) bonds, four C–H sigma (σC-H) bonds, and two C=C pi πC-C bonds

3. two C–C sigma (σC-C) bonds, four C–H sigma (σC-H) bonds, and two C=C pi πC-C bonds

4. two C–C sigma (σC-C) bonds, two C–H sigma (σC-H) bonds, and two C=C pi πC-C bonds

Subtopic:  Hybridisation & Structure of Carbon Compounds |
 85%
Level 1: 80%+
Hints

advertisementadvertisement

The correct number of σ and π bonds in the molecule CH3NO2 is:

σ (C - H) σ (C - N) σ (N - O) π (N=O) 
1. 1 1 1 3
2. 1 1 3 1
3. 1 3 1 3
4. 3 1 1 1
Subtopic:  Hybridisation & Structure of Carbon Compounds |
 91%
Level 1: 80%+
Hints