Study the diagram and answer the following questions. a) Which gas is being collected? b) Write the balanced chemical reaction. c) Which gas will be formed if conc. H₂SO₄ is kept instead of dilute H₂S

here are the answers to question 30:

30. Study the diagram and answer the following questions.

• a) Which gas is being collected in the gas jar? When granulated zinc reacts with dilute hydrochloric acid, hydrogen gas is produced. The gas being collected is $\boxed{\text{Hydrogen gas (H}_2\text{)}}$.

• b) Write down the balanced chemical reaction involved in this process. The reaction between zinc and dilute hydrochloric acid produces zinc chloride and hydrogen gas.

  $$\text{Zn(s)} + \text{2HCl(aq)} \rightarrow \text{ZnCl}_2\text{(aq)} + \text{H}_2\text{(g)}$$

  The balanced chemical reaction is $\boxed{\text{Zn(s)} + \text{2HCl(aq)} \rightarrow \text{ZnCl}_2\text{(aq)} + \text{H}_2\text{(g)}}$.

• c) Which gas will be formed if conc. H₂SO₄ is kept instead of dilute H₂SO₄ acid? If concentrated sulfuric acid (conc. H₂SO₄) is used instead of dilute sulfuric acid with zinc, the concentrated acid acts as an oxidizing agent. In this case, sulfur dioxide gas is formed, not hydrogen.

  $$\text{Zn(s)} + \text{2H}_2\text{SO}_4\text{(conc.)} \rightarrow \text{ZnSO}_4\text{(aq)} + \text{SO}_2\text{(g)} + \text{2H}_2\text{O(l)}$$

  The gas formed will be $\boxed{\text{Sulfur dioxide (SO}_2\text{)}}$.