Question

(A) Ram studied the reaction of Fe , mg , Al , and zn with dilute hydrochloric acid.
1) arrange the elements in decreasing order of reactivity.
2) state the observations on the basics of which he will arrange the elements in the order of reactivity.
(B) Why hydrogen gas not evolved when metals react with dilute nitric acid . What happens to nitric acid during the reaction.
(C) Name two metals that liberate hydrogen from dilute nitric acid.

Answer 1

Here you go! Hope this helps otherwise the text is clearly given in text book...

Answer 2

A)(1) Mg>Al>Zn>Fe

(2)

A vigorous reaction will take place between Mg and HCl and a lot of H2 will be evolved.

A partially vigorous reaction reaction will take place between Al and HCl and less amount of H2 is evolved as compared to Mg.

A moderate reaction will take place between Zn and HCl and H2 is evolved slowly.

A slow reaction will take place between Fe and HCl and H2 will be evolved very slowly...

B) HNO3 first reacts with metal(M) to form metal nitrate and also oxidizes itself to form nitrogen oxides and H2O.

Eg: 3Mg + 8HNO3 → 3Mg(NO3)2 + 2NO↑ + 4H2O

C)

Mg + 2HNO3 → Mg(NO3)2 + H2↑

Mn + 2HNO3 → Mg(NO3)2 + H2↑

* ☝Here HNO3 is super dilute...