Answer:
xii. B. Smelting
xiii. D. Carbon
Explanation:
Smelting is known to be a process by which a metal is gotten. It is gotten either as the element or as a simple compound. This is obtained from metal's ore by heating. The heating can be done ordinarily in the presence of oxidizing agents, like air, or reducing agents, carbon e.g coke.
Zinc is gotten after Zinc oxide is heated in the presence of carbon.
This process is smelting.
Concentrated tetraoxosulphate acid is a strong dehydrating agent. It has the ability to char wood, paper, or sugar, leaving a carbonaceous residue. The charring effect is as a result of the carbon that is found in the wood.
The acid sucks in the oxygen and hydrogen, leaving behind the carbon; this results in the charring effect.
