If is Avogadro's number, then number of valence electrons in 4.2 g of ions is: [1] — Mole Concept and Some Basic Concepts of Chemistry Chemistry Question

💡 Solution & Explanation

Moles of $N^{3-} = 4.2 / 14 = 0.3$ mol. <br>A nitrogen atom ($Z=7$) has 5 valence electrons. The $N^{3-}$ ion gains 3 more, totaling 8 valence electrons. <br>Total valence electrons $= 0.3 \times 8 \times N_A = 2.4 N_A$. [1]