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Q87 (NDA-I/2026) Science & Technology › Basic Science (Physics, Chemistry, Biology)

Consider the following :

I. AlCl3

II. NH3

III. BF3

IV. FeCl 3

How many of the above are Lewis acids?

Result
Your answer: —  Â·  Correct: C

Explanation

A Lewis acid is defined as a chemical species that can accept an electron pair. AlCl3 (Aluminum Chloride) and BF3 (Boron Trifluoride) are classic examples because their central atoms (Al and B) are electron-deficient, possessing only six electrons in their valence shells. FeCl3 (Ferric Chloride) also acts as a Lewis acid because the Fe3+ ion has vacant d-orbitals that can accept electron pairs from Lewis bases. Conversely, NH3 (Ammonia) is a Lewis base because the nitrogen atom has a lone pair of electrons available for donation. Therefore, three of the four listed compounds (I, III, and IV) are Lewis acids.

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SIMILAR QUESTIONS

CDS-I · 2025 · Q59 Relevance score: 0.77

Which one of the following contains all Lewis acids ?

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Consider the following 0.1 N acids: I. Acetic acid II. Perchloric acid II, Chloroacetic acid IV. Hydrochloric acid What is the sequence of these in terms of their increasing acid strength in water?