Question

The order of reactivity with oxygen is in the order:
A. $Zn > Al > Mg > Fe$
B. $Cu > Ag > Al > Au$
C. $Al > Zn > Mg > Fe$
D. $Fe > Mg > Al > Zn$

Answer 1

Every metal shows different reactivity on reacting with other elements. The more reactive metal when reacted with oxygen burns very vigorously. By observing the reaction, the metals are arranged in the order according to their reactivity with the oxygen.

Complete step by step answer:
The metal reacts with oxygen to form a metal oxide.The general reaction is shown below.
$Metal + oxygen \to metal oxide$
Example: $2Zn + {O_2} \to 2ZnO$
In this reaction, both oxidation and reduction take place simultaneously. The oxidation reaction takes place in the metal, the metal oxidized to form a positive ion.The reduction reaction takes place in the oxygen, the oxygen gets reduced to form an oxide ion.This reaction is known as a redox reaction.In this reaction, the metal is the reducing agent and oxygen is the oxidizing agent.The reactivity of the metal with oxygen is seen by how vigorous the reaction takes place. More Reactive metal will burn vigorously with oxygen while the metal with low reactivity will react slowly or will not react.According to the reactivity of metal, they are arranged in the reactivity series of metals. The reactivity series is the list of metals placed according to their reactivity with the oxygen.From the given element, aluminium is the most reactive element and copper is the least reactive.
Thus, the order of reactivity with oxygen is in the order
$Al > Zn > Mg > Fe$

So, the correct answer is Option C.

Note:
The reactivity series of metal is somehow the same as the electrochemical series as the reaction of metal with oxygen is related to the loss of electrons. Silver, gold and platinum do not show reactivity with oxygen.