In NO3- ion, the number of bond pairs and lone pairs of electrons on nitrogen atom are

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Ques: In NO3- ion, the number of bond pairs and lone pairs of electrons on nitrogen atom are

(a) 2, 2 

(b) 3, 1 

(c) 1,3 

(d) 4, 0

Sol: (d) In N-atom, numbers of valence electron = 5.

Due to the presence of 1 negative charge on nitrate ion, number of valence electrons = 5 + 1 = 6. One Oxygen- atom forms two bonds (= bond) and two O-atom are shared with two electrons of N-atom.

Thus, 3 Oxygen-atoms are shared with 8 electrons of N-atom.

Number of bond pairs (or shared pairs) = 4.

N umber of lone pairs = 0.

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