NEET 2018 · ChemistryPrevious Year Question
Which one of the following elements is unable to form ion?
Answer: (A) . \textbf{Answer:} (A) \textbf{Solution:} Boron has no vacant d-orbitals in its valence shell, so it cannot expand its covalency beyond 4 (cannot expand its octet).
- A.✓
- B.
- C.
- D.
Correct Answer
(A)
Solution & Explanation
\textbf{Answer:} (A) \textbf{Solution:} Boron has no vacant d-orbitals in its valence shell, so it cannot expand its covalency beyond 4 (cannot expand its octet). Hence it cannot form an octahedral ion, unlike , and which have accessible d-orbitals.
🎯
43,000+ questions in हिंदी & English · one-tap toggle
Open →📚Practice all NEET Chemistry PYQs chapter-wise →💡Don't get it? Learn the Chemical Bonding concepts →Practice NEET 2018 Chemistry — free, with instant solutions
The app builds a daily goal from your weak topics and brings each question back just before you forget it — so what you solve today turns into marks on exam day.
More NEET PYQ solutions
ChemIdentify the suitable reagent for the following conversion: C6H5COOCH3 -> C6H5CHO (methyl benzoate to benzaldehyde)ChemThe correct order of decreasing acidity of the following aliphatic acids isChemThe major product of the following reaction is: 4-oxo-4-phenylbutanenitrile C6H5-CO-CH2-CH2-CN is treated with (i) CH3MgBr (excess) and then (ii) H3O+.ChemOut of the following complex compounds, which compound will have the minimum conductance in solution?ChemWhich of the following are paramagnetic? A. [NiCl4]^2- B. Ni(CO)4 C. [Ni(CN)4]^2- D. [Ni(H2O)6]^2+ E. Ni(PPh3)4ChemThe correct order of the wavelength of light absorbed by the following complexes is: A. [Co(NH3)6]^3+ B. [Co(CN)6]^3- C. [Cu(H2O)4]^2+ D. [Ti(H2O)6]^3+ChemThe correct order of decreasing basic strength of the given amines is: (N-ethylethanamine = (C2H5)2NH; ethanamine = C2H5NH2; N-methylaniline = C6H5NH(CH3); benzenamine/aniline = C6H5NH2)ChemPredict the major product P in the following sequence of reactions. The starting material is 1-methylcyclopent-1-ene: (i) HBr, benzoyl peroxide; (ii) KCN; (iii) Na(Hg)/C2H5OH P (major). The structures of the options (A)-(D) are shown in the image below: