Question

Burn copper turnings in oxygen for few minutes and observe. 1. Why does the surface of copper turnings become black on heating? 2. Name the product formed. 3. What will happen if hydrogen gas is allowed to pass over it? 4. Write both the chemical equations. 5. Name the substance oxidised and reduced during the process. 6. Give one name to the whole process

Answer 1

Answer:

Copper is one of the few metals that can occur in nature in a directly usable metallic form (native metals). This led to very early human use in several regions, from c. 8000 BC. Thousands of years later, it was the first metal to be smelted from sulfide ores, c. 5000 BC, the first metal to be cast into a shape in a mold, c. 4000 BC and the first metal to be purposefully alloyed with another metal, tin, to create bronze, c. 3500 BC.[4]

In the Roman era, copper was principally mined on Cyprus, the origin of the name of the metal, from aes сyprium (metal of Cyprus), later corrupted to сuprum (Latin), from which the words derived, coper (Old English) and copper, first used around 1530.[5]