Three metal samples of magnesium, aluminium and iron were taken and
rubbed with sand paper. These samples were then put separately in test
tubes containing dilute hydrochloric acid. Thermometers were also
suspended in each test tube so that their bulbs dipped in the acid. The
rate of formation of bubbles was observed. The above activity was
repeated with dilute nitric acid and the observations were recorded.
Answer the following questions :
(a) When activity was done with dilute hydrochloric acid, then in
which one of the test tubes was the rate of formation of bubbles the
fastest and the thermometer showed the highest temperature ?
(b) Which metal did not react with dilute hydrochloric acid ? Give
reason.
(c) (i) Why is hydrogen gas not evolved when a metal reacts with
dilute nitric acid ? Name the ultimate products formed in the
reaction.
OR
(c) (ii) Name the type of reaction on the basis of which reactivity of
metals is decided. You have two metals X and Y. How would
you decide which is more reactive than the other?