Question 1

Zinc can be extracted from its ores, smithsonite ( $ZnCO3\text{ZnCO}_3$ ) and zinc blende ( $ZnS\text{ZnS}$ ).

Smithsonite decomposes on heating to produce zinc oxide ( $ZnO\text{ZnO}$ ). The zinc oxide is then reduced by carbon in a furnace:

\text{ZnO} + \text{C} \rightarrow \text{Zn} + \text{CO}

Identify which species is reduced in this reaction, and explain your choice in terms of oxygen transfer.

When zinc blende ( $ZnS\text{ZnS}$ ) is roasted in air, sulfur dioxide ( $SO2\text{SO}_2$ ) is produced as a waste gas. Write a chemical equation to show how sulfur dioxide reacts with water to form an acidic solution, and state one harmful effect of acid rain on the environment.

A mining company processes a sample of smithsonite containing $g750\text{ g}$ of $ZnCO3\text{ZnCO}_3$ . Calculate the maximum mass of zinc ( $Zn\text{Zn}$ ) that can be obtained from this sample. (Relative atomic masses: $Zn=65\text{Zn} = 65$ , $C=12\text{C} = 12$ , $O=16\text{O} = 16$ )