Question

A student took two tubes containing 2 mL of dilute hydrochloric acid and added zinc granules to test tube (A) and solid sodium carbonate to test tube (B) as shown below:
The correct observation would be
(1) Rapid reaction in both the test tubes
(2) Slow reaction in (A) and rapid reaction in (B)
(3) Rapid reaction in (A) but a slow reaction in (B)
(4) No reaction in any of the test tubes

Answer 1

(2) Slow reaction in (A) and rapid reaction in (B)

Explanation:

Slow reaction - Test Tube A:

When the student adds Zinc granule to diluted hydrochloric acid, the zinc displaces the hydrogen to form hydrogen gas and zinc chloride, a salt. Hydrogen gas is released. This reaction is slow with diluted HCl, but fast with concentrated HCl.

Rapid reaction  - Test Tube B:

When hydrochloric acid is added to sodium carbonate, the reaction produces large quantities of carbon dioxide gas, water and table salt. This is a rapid reaction and you can see the brisk effervescence of the CO2 gas escaping.

Answer 2

Answer:

Explanation:

rapid reaction occurs in both test tubes because both ,zinc granules and sodium carbonate shows metalic nature.