Question

Number of valency electrons in 4.2 gram of $N_3^-$ ion is
(a) $4.2 N_A$
(b) $0.1 N_A$
(c) $1.6 N_A$
(d) $3.2 N_A$

Answer 1

may be her answer is

c

Answer 2

the answer is

(c) $1.6 N_A$

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