JEE Main 2018ChemistryEnvironmental ChemistryMediumMCQ

JEE Main 2018 — Environmental Chemistry Question with Solution

JEE Main 2018 (08 Apr)

Question

The recommended concentration of fluoride ion in drinking water is up to 1 ppm as fluoride ion is required to make teeth enamel harder by converting 3Ca3PO42.CaOH2 to:

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Show full solutionCorrect option: D
Correct answer
D3Ca3PO42.CaF2

Step-by-step explanation

The recommended concentration of fluoride ion in drinking water is up to 1 ppm as fluoride ion is required to make teeth enamel harder by converting

 [ 3 Ca3(PO4)2.Ca(OH)2 ] to [ 3 Ca3(PO4)2.CaF2 ].

[ 3 Ca3(PO4)2.Ca(OH)2 ] + 2 F-  → [ 3 Ca3(PO4)2.CaF2 ]

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About this question

This is a previous-year question from JEE Main 2018, covering the Environmental Chemistry 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.