Which of the two structures $(A)$ and $(B)$ given below is more stabilised by resonance.
Explain $$\mathop {C{H_3}COOH}\limits_{(A)} $$ and $$\mathop {C{H_3}CO{O^\Theta }}\limits_{(B)} $$
Resonating structures of (A) and (B) are as follows
Structure (II) is less stable than structure (I) because later carries separation of positive and negative charges. Therefore, contribution of structure (II) is less than that of (I) towards the resonance hybrid of compound (A), i.e., $\mathrm{CH}_3 \mathrm{COOH}$. On contrary, structure (III) and (IV) are of equal energy and hence contribute equally towards the resonance hybrid of compound ( $B$ ). Therefore, structure $(B)$ is more stable than structure $(A)$ i.e., $\mathrm{CH}_3 \mathrm{COO}^{\ominus}$.
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 reaction when dissolved in it | 1. | Steam distillation |
| B. | Liquid that decomposes at its boiling point | 2. | Fractional distillation |
| C. | Steam volatile liquid | 3. | Simple distillation |
| D. | Two liquids which have boiling points close to each other | 4. | Distillation under reduced pressure |
| E. | Two liquids with large difference in boiling points. | 5. | Crystallisation |
| Column I | Column II | ||
|---|---|---|---|
| A. | Two solids which have different solubilities in a solvent and which do not undergo reaction when dissolved in it | 1. | Crystallisation |
| B. | Liquid that decomposes at its boiling point | 2. | Distillation under reduced pressure |
| C. | Steam volatile liquid | 3. | Steam distillation |
| D. | Two liquids which have boiling points close to each other | 4. | Fractional distillation |
| E. | Two liquids with large difference in boiling points. | 5. | Simple distillation |
Match the terms mentioned in Column I with the terms in Column II.
| Column I | Column II | ||
|---|---|---|---|
| A. | Carbocation | 1. | Cyclohexane and 1-hexene |
| B. | Nucleophile | 2. | Conjugation of electrons of C-H$$\sigma$$ bond with empty p-orbital present at adjacent positively charged carbon |
| C. | Hyperconjugation | 3. | sp$$^2$$ hybridised carbon with empty p-orbital |
| D. | Isomers | 4. | Ethyne |
| E. | sp-hybridisatioin | 5. | Species that can receive a pair of electrons |
| F. | Electrophile | 6. | Species that can supply a pair of electrons |
A - 3, B - 6, C - 2, D - 1, E - 4, F - 5
| Column I | Column II | Explanation | |
|---|---|---|---|
| A. | Carbocation | sp$$^2$$-hybridised carbon with empty p-orbital | H$$_3$$C$$^+$$ is carbocation. Loss of e$$^-$$ makes its p-orbitals empty (sp$$^2$$-hybridised carbon) |
| B. | Nucleophile | Species that can supply a pair of electron | Nucleus loving i.e., having negative charge or excess of electrons |
| C. | Hyperconjugation | Conjugation of electrons of $\mathrm{C}-\mathrm{H} \sigma$ bond with empty $p$-orbital present at adjacent positively charged carbon | |
| D. | Isomers | Cyclohexane and 1-hexene | Same molecular formula but different structures |
| E. | sp-hybridisatioin | Ethyne | HC = CH (sp-hybridisation) |
| F. | Electrophile | Species that receive a pair of electron | Electron loving i.e., positive charge or lack of electrons |
Match column I with column II.
| Column I | Column II | ||
|---|---|---|---|
| A. | Dumas method | 1. | AgNO$$_3$$ |
| B. | Kjeldahl's method | 2. | Silica gel |
| C. | Carius method | 3. | Nitrogen gel |
| D. | Chromatography | 4. | Free radicals |
| E. | Homolysis | 5. | Ammonium sulphate |
| Column I | Column II | Explanation | |
|---|---|---|---|
| A. | Dumas method | Nitrogen gel | Used for N containing compounds |
| B. | Kjeldahl's method | Ammonium sulphate | Nitrogen converts to ammonium sulphate |
| C. | Carius method | AgNO$$_3$$ | Compound is heated in presence of AgNO$$_3$$ |
| D. | Chromatography | Silica gel | Adsorbent used is silica gel |
| E. | Homolysis | Free radical | Free radicals are formed by homolytic fission |
Match the intermediates given in Column I with their probable structure in Column II.
| Column I | Column II | ||
|---|---|---|---|
| A. | Free radical | 1. | Trigonal planar |
| B. | Carbocation | 2. | Pyramidal |
| C. | Carbanion | 3. | Linear |
A - 1, B - 1, C - 2
| Column I | Column II | Explanation | |
|---|---|---|---|
| A. | Free radical | Trigonal planar | Free radicals are formed by homolytic fission e.g... ${ }^{\Upsilon} \mathrm{H}_3$ hybridisation $s p^2$ |
| B. | Carbocation | Trigonal planar | Formed by heterolytic fission when carbon is attached to a more electronegative atom |
| C. | Carcanion | Pyramidal | Formed by heterolytic fission when carbon is attached to more electropositive atom e.g.. $\mathrm{CH}_3^{-}$hybridisation $\mathrm{sp}^3$ |