HARD
9th ICSE
IMPORTANT
Earn 100

Based on the reactions of water on metals, arrange the following metals in increasing order of reactivity:

Iron, sodium magnesium, zinc, calcium.

Important Questions on Study of the First Elements-Hydrogen

HARD
9th ICSE
IMPORTANT
 Hydrogen is evolved when dilute HCl reacts with magnesium, but nothing happens in the case of mercury and silver. Explain.
HARD
9th ICSE
IMPORTANT
Steam can react with a metal and a non-metal to liberate hydrogen. Give the necessary conditions and equations for the same.
HARD
9th ICSE
IMPORTANT
Hydrogen is obtained by displacement from dilute sulphuric acid. Write equations using zinc and Iron. Why does not copper show similar behaviour?
HARD
9th ICSE
IMPORTANT
Hydrogen is obtained by displacement from dilute hydrochloric acid. Write equations using zinc and Iron. Why does not copper show similar behaviour?
HARD
9th ICSE
IMPORTANT

Give a reason for the following:

Though lead is above hydrogen in the activity series, it does not react with dilute hydrochloric acid or dilute sulphuric acid.

HARD
9th ICSE
IMPORTANT

Give a reason for the following:

Potassium and sodium are not used for reaction with dilute hydrochloric acid or dilute sulphuric acid in the laboratory preparation of hydrogen.

HARD
9th ICSE
IMPORTANT
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?
HARD
9th ICSE
IMPORTANT
Complete and balance the following reaction:

Na + H2O  _____ + _____