Which of the following options are correct for the reaction? 2 Au ( CN ) 2 - ( aq ) + Zn ( s ) → 2 Au ( s ) + Zn ( CN ) 4 2 - ( aq ) A. Redox reaction B. Displacement reaction C. Decomposition reaction D. Combination reaction Choose the correct answer from the options given below:

Step-by-step solution

Gold is then extracted from this complex by displacement technique by using a more electropositive zinc metal. In this method, zinc ( Zn ) acts as a reducing agent and it reduces Au + to Au and itself gets oxidized from Zn to Zn + 2 ions which combine with CN - ions and form soluble complex, sodium tetracyanozincate (II). 2 Au ( CN ) 2 - aq + Zn s → 2 Au s + Zn ( CN ) 4 2 - aq