Online CBSE NEET 2017 Online Solution of Chemistry =4

These are MCQs of CBSE NEET 2017 with Solutions of chemistry = 4

1. The correct statement regarding electrophile is :-

• Electrophile is a negatively charged species and can form a bond by accepting a pair of electrons from another electrophile
• Electrophiles are generally neutral species and can form a bond by accepting a pair of electrons from a nucleophile
• Electrophile can be either neutral or positively charged species and can form a bond by accepting a pair of electrons from a nucleophile
• Electrophile is a negatively charged species and can form a bond by accepting a pair of electrons from a nucleophile

2. A gas is allowed to expand in a well insulated container against a constant external pressure of 2.5atm from an initial volume of 2.50 L to a final volume of 4.50L. The change in internal energy ΔU of the gas in joules will be:-

• –500J
• –505J
• +505J
• 1136.25J

3. Which of the following reactions is appropriate for converting acetamide to methanamine ?

• Hoffmarnn hypobromamide reaction
• Stephens reaction
• Gabriels phthalimide synthesis
• Carbylamine reaction

4. With respect to the conformers of ethane, which of the following statements is true ?

• Bond angle changes but bond length remains same
• Both bond angle and bond length change
• Both bond angles and bond length remains same
• Bond angle remains same but bond length changes

5. In which pair of ions both the species contain S–S bond?

• (S₄O₆)^2-, (S₂O₃)^2-
• (S₂O₇)^2-, (S₂O₈)^2-
• (S₄O₆)^2-, (S₄O₇)^2-
• (S₄O₇)^2-, (S₄O₃)^2-

6. It is because of inability of ns2 electrons of the valence shell to participate in bonding that:-

• Sn²⁺ is oxidising while PbSn⁴⁺ is reducing
• Sn²⁺ and Pb²⁺ are both oxidising and reducing
• Sn⁴⁺ is reducing while Pb⁴⁺ is oxidising
• Sn²⁺ is reducing while Pb⁴⁺ is oxidising

7. Correct increasing order for the wavelengths of absorption in the visible region the complexes of Co³⁺ is :-

• [Co(H₂O)₆]³⁺, [Co(en)₃]³⁺, [Co(NH₃)₆]³⁺
• [Co(H₂O)₆]³⁺, [Co(NH₃)₆]³⁺, [Co(en)₃]³⁺
• [Co(NH₃)₆]³⁺, [Co(en)₃]³⁺, [Co(H₂O)₆]³⁺
• [Co(en)₃]³⁺, [Co(NH₃)₆]³⁺, [Co(H₂O)₆]³⁺

8. Consider the reactions :-

• (1) A-Methoxymethane, X-Ethanol, Y-Ethanoic acid, Z-Semicarbazide.
• A - Ethanal , X - Ethanol , Y - But - 2 - enal , Z - Semicarbazone
• A-Ethanol, X- Acetaldehyde, Y- Butanone, Z- Hydrazone
• A-Methoxymethane, X-Ethanoic acid, Y-Acetate ion, Z-hydrazine

9. Of the following, which is the product formed when cyclohexanone undergoes aldol condensation followed by heating ?:-

• 

10. Which of the following pairs of species have the same bond order ?

• O₂, NO⁺
• CN^–, CO
• N₂ , (O₂)^2-
• CO, NO