JEE Main 2021 — S Block Elements Question with Solution
From: JEE Main 2021 (Online) 20th July Morning Shift
Question
Choose an option
Show full solutionCorrect option: B
Step-by-step explanation
(A) Both are acidic in nature.
B(OH)3 is orthoboric acid. It can accept a pair of electrons from Lewis bases and hence, act as Lewis acid.
H3PO3 is (phosphorus acid) diprotic acid as it readily ionises two protons.
(B) B(OH)3 is acidic and Al(OH)3 is amphoteric in nature.
(C) Both NaOH and Ca(OH)2 are basic hydroxides.
(D) Both Be(OH)2 and Al(OH)3 are amphoteric hydroxides.
Hence, only B(OH)3 and Al(OH)3 have different nature.
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This is a previous-year question from JEE Main 2021, covering the S Block Elements chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.