The correct answer is D. All the above.
Melamine is a white, crystalline solid that is used in a variety of products, including resins, adhesives, and fertilizers. It is obtained from calcium carbide, which is produced by heating calcium carbonate with coke. Formaldehyde is a colorless, flammable gas that is used in a variety of products, including plastics, resins, and adhesives. It is prepared synthetically from methane, which is a natural gas. When melamine is reacted with formaldehyde, it forms melamine-formaldehyde resin, which is a hard, durable material that is used in a variety of products, including countertops, furniture, and laminate flooring.
Here is a more detailed explanation of each option:
- Option A: Melamine is obtained from calcium carbide. Calcium carbide is a white, crystalline solid that is produced by heating calcium carbonate with coke. Coke is a solid fuel that is produced from coal. When calcium carbonate is heated with coke, it forms calcium carbide and carbon dioxide. The calcium carbide is then reacted with water to form melamine.
- Option B: Formaldehyde is prepared synthetically from methane. Methane is a colorless, odorless, flammable gas that is the simplest alkane. It is the main component of natural gas. When methane is heated to high temperatures, it reacts with oxygen to form carbon monoxide and hydrogen. The carbon monoxide is then reacted with hydrogen to form formaldehyde.
- Option C: The melamine when reacted with formaldehyde forms the melamine-formaldehyde resin. Melamine is a white, crystalline solid that is used in a variety of products, including resins, adhesives, and fertilizers. Formaldehyde is a colorless, flammable gas that is used in a variety of products, including plastics, resins, and adhesives. When melamine is reacted with formaldehyde, it forms melamine-formaldehyde resin, which is a hard, durable material that is used in a variety of products, including countertops, furniture, and laminate flooring.