The correct order of decreasing stability of the following carbocations is:
I | \( \begin{aligned} &~~~~~~~~~~~~\oplus\\ & CH_3 - CH-CH_3 \end{aligned}\) |
II | \( \begin{aligned} &~~~~~~~~~~~~\oplus\\ & CH_3 - CH-OCH_3\end{aligned}\) |
III | \( \begin{aligned} & ~~~~~~~~~~~~\oplus\\ &CH_3 - CH-CH_2- OCH_3\end{aligned}\) |
1. | II > I > III | 2. | I > II > III |
3. | II < I < III | 4. | I < II < III |
The correct IUPAC name for
is _____.
1. 2-Ethyl-3-methylpentane
2. 3,4-Dimethylhexane
3. 2-sec-Butylbutane
4. 2,3-Dimethylbutane
Which of the following carbon marked with asterisk is expected to have greatest positive charge?
1. | 2. | ||
3. | 4. |
Which carboxylate ion among the following is the most stable?
1. | 2. | ||
3. | 4. |
Electrophilic addition reactions proceed in two steps. The first step involves the addition of an electrophile. The major intermediate formed in the first step is -
?
1. carbanion
2. carbocation
3. carbocation
4. carbanion
The correct representation involving heterolytic fission of among the following is:
1. | |
2. | |
3. | |
4. |
The addition of HCl to an alkene proceeds in two steps. The first step is the attack of H+ ion on the double bond portion. The same can be shown as-
1. | 2. | ||
3. | 4. | All of these are possible |
Match the type of mixture of compounds in Column I with the technique of separation/purification given in column II.
Column I | Column II |
A. Two solids which have different solubilities in a solvent and which do not undergo a reaction when dissolved in it | 1. Steam distillation |
B. Liquid that decomposes at its boiling point | 2. Fractional distillation |
C. Steam volatile liquid | 3. Crystallisation |
D. Two liquids that have boiling points close to each other | 4. Distillation under reduced pressure |
Codes:
A | B | C | D | |
1. | 3 | 4 | 1 | 2 |
2. | 1 | 2 | 3 | 4 |
3. | 1 | 4 | 3 | 2 |
4. | 4 | 1 | 3 | 2 |
Match the terms mentioned in Column I with the terms in Column II.
Column I |
Column II |
A. Carbocation |
1. Species that can receive a pair of electrons |
B. Nucleophile |
2. Conjunction of electrons of bond with the empty p-orbital present in adjacent positively charged carbon |
C. Hyperconjugation |
3. hybridised carbon with empty p-orbital |
D. Electrophile |
4. Species that can donate a pair of electrons |
Codes:
Options: | A | B | C | D |
1. | 3 | 4 | 2 | 1 |
2. | 1 | 2 | 3 | 4 |
3. | 1 | 4 | 3 | 2 |
4. | 4 | 1 | 3 | 2 |
Match Column I with Column II.
Column I | Column II |
A. Dumas method | 1. AgNO3 |
B. Kjeldahl’s method | 2. Silica gel |
C. Carius method | 3. Nitrogen gel |
D. Chromatography | 4. Ammonium sulphate |
Codes:
A | B | C | D | |
1. | 3 | 4 | 1 | 2 |
2. | 1 | 2 | 3 | 4 |
3. | 1 | 4 | 3 | 2 |
4. | 4 | 1 | 3 | 2 |