Question

Consider the following statements
1) Metal X displace Y from its salt solution but
not hydrogen from water or dilute acid.
II) Metals Z and A both release hydrogen with
dilute acids.
III) Metal Z releases hydrogen with nitric acid
but metal A does not.
IV) Metal A is not able to displace metal Z
from its salt solution
On the basis of above observations, the order
of reactivity of these metals is​

Answer 1

Answer:

option d

Explanation:

Answer 2

The order of reactivity of these metals is Z > A > X > Y

The question uses the Reactivity series of metal concept.

Reactivity series of metals definition:

• The reactivity series of metals is a series in Chemistry that gives the order of reactivity of metals.
• A metal higher up in the reactivity series will be able to displace a metal lower in the reactivity series from its salt solution.

Which metals can displace Hydrogen from acids or water ?

• Since H is towards the end of the reactivity series, most metals can displace Hydrogen from a dilute acid or water.

• Copper, Mercury, Silver and Gold lies below Hydrogen. So, they cannot displace Hydrogen.

Let us analyze the information given in the question,  

1. Since Metal X can displace metal Y, therefore X is higher in series than Y. But, since X cannot displace Hydrogen, that means X is below Hydrogen in the series. So Y is also below Hydrogen.
2. Metals Z and A both release H from dilute acids, so both metals A and Z are above Hydrogen.
3. Only highly reactive metals like Mg, Mn and Zn release Hydrogen from nitric acid. Since metal A cannot, therefore Z is higher in series than A.
4. Since metal A cannot displace Z, therefore reactivity of Z is more than A.

Based on these observations, we can say that Z is the most reactive, followed by A, then X and then Y. The order of reactivity of these metals is Z > A > X > Y