A metal is treated with dilute sulphuric acid. The gas evolved is collected by the method shown in the figure:
(a) Name the gas evolved:
(i) Hydrogen
(ii) Oxygen
(iii) Sulphur dioxide gas
(iv) Carbon dioxide
Ans.
When a metal is reacted with dilute sulphuric acid, hydrogen gas is evolved.
The reaction is as follows:
M + H 2 SO 4 →MSO 4 + H 2 ↑
So, the correct answer is (i) Hydrogen gas.
( b) Is the gas lighter or heavier than air? How will you test the gas?
Ans.
Hydrogen gas is lighter than air .
Test for presence of hydrogen gas:
- When a burning splinter is brought near the gas, it burns with a pop sound.
- This pop sound is produced due to the burning of hydrogen gas.
(c) If the metal used above is zinc then write the chemical equation for the evolution of gas.
Ans.
The reaction is as follows:
Zn(s) + H 2 SO 4 (dil) → ZnSO 4 (aq) + H 2 (g)↑
(d) What nature of hydrogen is used as a fuel in rocket:
(i) solid
(ii) liquid
(iii) gaseous
(iv) all of the above
Ans.
Liquid hydrogen is used as a fuel in rockets.
So, the correct
answer is (ii) Liquid