An aqueous solution of is treated with excess . How many moles of precipitate will be formed per mol — Coordination Compounds Chemistry Question

💡 Solution & Explanation

Cobalt(III) has a secondary valency (coordination number) of 6. To satisfy this, five $NH_3$ molecules and one $Cl^-$ ion must be inside the coordination sphere, giving the formula $[Co(NH_3)_5Cl]Cl_2$. Thus, 2 moles of $Cl^-$ ions are outside the sphere and will precipitate as $AgCl$.