Chemistry
Hydrogen is obtained by displacement from
(a) dilute sulphuric acid
(b) dilute hydrochloric acid
Write equations using zinc and iron.
Why does not copper show similar behaviour?
Answer
(a) dilute sulphuric acid
Zn + H2SO4 (dil.) ⟶ ZnSO4 + H2 ↑
Fe + H2SO4 (dil.) ⟶ FeSO4 + H2 ↑
(b) dilute hydrochloric acid
Zn + 2HCl (dil.) ⟶ ZnCl2 + H2 ↑
Fe + 2HCl (dil.) ⟶ FeCl2 + H2 ↑
Zinc and iron are above hydrogen in activity series of metals whereas copper is below hydrogen in the series. As metals below hydrogen cannot displace it from dilute acids hence, copper does not show similar behaviour as zinc and iron.
Related Questions
Hydrogen is evolved when dilute HCl reacts with magnesium, but nothing happens in the case of mercury and silver. Explain.
Steam can react with a metal and a non-metal to liberate hydrogen. Give the necessary conditions and equations for the same.
Give a reason for the following
(a) Though lead is above hydrogen in the activity series, it is not used to prepare hydrogen.
(b) Potassium and sodium are not used for reaction with dilute hydrochloric acid or dilute sulphuric acid in the laboratory preparation of hydrogen.
Name two alkalies that can displace hydrogen. Give balanced equations for the same. Why are the metals you have used considered to have unique nature?