Question

Equal length of magnesium ribbons is taken in two test tubes ‘A’ and ‘B’ H2SO4 is added to test tube ‘A’ and H2CO3 in the test tube ‘B’ in equal amounts: a) Identify the test tube showing vigorous reaction. b) Give reason to support your answer. c) Name the gas liberated in both the tubes. How will you prove its liberation? d) Write chemical equations for both reactions. e) Out of the two acids taken above (i) Which one will have lower pH value? (ii) Lower H+ concentration respectively:

Answer 1

Explanation:

Given -

• Equal length of magnesium ribbons is taken in two test tubes ‘A’ and ‘B’ H2SO4 is added to test tube ‘A’ and H2CO3 in the test tube ‘B’ in equal amounts.

To Find -

1. Identify the test tube showing vigorous reaction.
2. Give reason to support your answer.
3. Name the gas liberated in both the tubes. How will you prove its liberation.
4. Write chemical equation for both reaction.
5. Out of two acid taken above (i) which one will lower pH value. (ii) Lower H+ concentration respectively.

Solution :-

1)

Test Tube ‘A’ shows vigorous reaction.

2)

Test Tube ‘A’ shows vigorous reaction because it contains strong acid which react with magnesium fastly as compared to other acid taken in Test Tube ‘B’.

3)

Hydrogen gas is liberated in both the test tubes.

we can proof the liberation of hydrogen gas by bringing a burning candle near it. The gas present in reaction (hydrogen) burns with ‘pop’ sound.

4)

When magnesium reacts with sulphuric acid then it forms magnesium sulphate and hydrogen gas is realesed.

Chemical equation :-

Mg + H2SO4 → MgSO4 + H2

When magnesium reacts with carbonic acid then it forms magnesium carbonate and hydrogen gas is released.

Chemical equation :-

Mg + H2CO3 → MgCO3 + H2

5)

(i) H2SO4 has lower pH value because it is more acidic.

(ii) H2CO3 has lower H+ concentration because strong acid releases H+ fastly as compared to weak acid.

Answer 2

1)In test tube A=H2SO4(strong acid)

in test tube B=H2CO3( weak acid)

so,the reaction take place vigorous in strong acid.

hence, In test tube A the reaction take place vigorous .

2)The gas which is elaborate is hydrogen gas (H2).

when hydrogen gas is taken to the burning candle it produce pop sound.

By this property we can check.

3)In test tube A

H2SO4+Mg----->MgSO4+H2

in test tube B

H2CO3+Mg----->MgCO3+H2

hope it's helpful for you