JEE · NEET Previous Year Question

$4\text{Ag}\text{(}s\text{)}+8{\text{CN}}^{-}\text{(}\text{aq}\text{)}+2H_{2}O\text{(}\text{aq}\text{)}+O_2\text{(}g\text{)}\text{⟶}4{\left(\text{Ag}\text{(}\text{CN}{\text{)}}_2\right)}^{-}\text{(}\text{aq}\text{)}+4^{-}\text{OH}\text{(}\text{aq}\text{)}$
The above reaction represents the process of concentration of ore in the extraction of silver. This process is

Topic: JEE PYQ

Answer: A. Full step-by-step solution below.