Question 13 Marks
Two ores A and B were taken. On heating ore A gives $CO _2$ whereas, ore B gives $SO _2$. What steps will you take to convert them into metals?
Answer
View full question & answer→Since the ore ‘A’ of the metal gives $CO _2$ upon heating, it is some metal carbonate ($MCO_3$). It can be converted to the metallic form as follows:Calcination:
$\text{MCO}_3\text{(s)}\xrightarrow{\text{heat}}\text{MO(s)}+\text{CO}_2\text{(g)}$
Smelting:
$\text{MO}\text{(s)} +\text{C(s)}\xrightarrow{\text{heat}}\text{M(s)}+\text{CO}\text{(g)}\\ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{(coke)}$
Since the ore ‘Y’ of the metal gives $SO _2$ upon heating, it can be some metal sulphide (MS). It can be converted to the metallic form as follows:Roasting:
$2\text{MS}\text{(s)}+3\text{O}_2\text{(g)}\rightarrow2\text{MO(s)}+2\text{SO}_2\text{(g)}$
Reduction:
$\text{MO}\text{(s)}+\text{C}\text{(s)}\rightarrow\text{M(s)}+\text{CO}\text{(g)}\\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{(coke)}$
$\text{MCO}_3\text{(s)}\xrightarrow{\text{heat}}\text{MO(s)}+\text{CO}_2\text{(g)}$
Smelting:
$\text{MO}\text{(s)} +\text{C(s)}\xrightarrow{\text{heat}}\text{M(s)}+\text{CO}\text{(g)}\\ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{(coke)}$
Since the ore ‘Y’ of the metal gives $SO _2$ upon heating, it can be some metal sulphide (MS). It can be converted to the metallic form as follows:Roasting:
$2\text{MS}\text{(s)}+3\text{O}_2\text{(g)}\rightarrow2\text{MO(s)}+2\text{SO}_2\text{(g)}$
Reduction:
$\text{MO}\text{(s)}+\text{C}\text{(s)}\rightarrow\text{M(s)}+\text{CO}\text{(g)}\\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \text{(coke)}$