The most suitable method used for the separation of 1:1 mixture of ortho and para-nitrophenols is:
1. | Chromatography | 2. | Crystallization |
3. | Steam distillation | 4. | Sublimation |
The IUPAC name of the compound is:
1. 5-formylhex-2-en-3-one
2. 5-methyl-4-2-en-5-el
3. 3-keto-2-methylhex-5-enal
4. 3-keto-2-methylhex-4-enal
The correct statement regarding electrophile is :
1. | Electrophile is a negatively charged species and can form a bond by accepting a pair of electrons from another electrophile |
2. | Electrophiles are generally neutral species and can form a bond by accepting a pair of electrons from a nucleophile |
3. | Electrophiles can be either neutral or positively charged species and can form a bond accepting a pair of electrons from a nucleophile |
4. | Electrophile is a negatively charged species and can form a bond by accepting a pair of electrons from a nucleophile |
With respect to the conformers of ethane, which of the following statements is true?
1. | Bond angle changes but bond length remains the same |
2. | Both bond angle and bond length change |
3. | Both bond angle and bond length remain the same |
4. | Bond angle remains the same but the bond length changes |
The correct order with respect to –I effect of the substituents is:
(R = alkyl)
1. –NH2 > –OR < –F
2. –NR2 < –OR < –F
3. –NH2 > –OR > –F
4. –NR2 > –OR > –F
The most stable carbocation among the following is:
1. | 2. | ||
3. | 4. |
The correct statement about the SN1 reaction is:
1. | 100 % racemisation. |
2. | Inversion more than retention leads to partial racemisation. |
3. | 100 % retention. |
4. | 100 % Inversion. |
Which of the following statements is not correct for a nucleophile?
1. Nucleophile is a Lewis acid.
2. Ammonia is a nucleophile.
3. Nucleophiles attack low electron density sites.
4. Nucleophiles are not electron-seeking.
Two possible stereo-structures of CH3CHOH.COOH, that are optically active, called:
1. | Diastereomers | 2. | Atropisomers |
3. | Enantiomers | 4. | Mesomers |
In Duma's method for estimation of nitrogen, 0.25 g of an organic compound gave 40 mL of nitrogen collected at 300 K temperature and 725 mm pressure. If the aqueous tension at 300 K is 25 mm, the percentage of nitrogen in the compound is:
1. | 17.36 | 2. | 18.20 |
3. | 16.76 | 4. | 15.76 |