Carbon discovered in Prehistoric times.. Discoverer will probably never be known
Answer:
D. Sweat evaporates from your skin
Explanation:
A physical change is a reversible process, no new substance is formed. A physical change does not affect the chemical composition of a substance.
Sweat evaporation from the skin is a physical change, because the change that occur is merely a change of state, Liquid to Gaseous state, no new substance is formed.
Answer: I believe the answer you are looking for is 0.02180
Luster is the term- means the shininess of the metal
This can be done through electrolysis. Electrolysis is the separation of a substance into two or more substances that may differ from each other and from the original substance by passing an electric current through a solution that contains ions.
In the case of copper, we use a copper (II) sulphate solution which we put in a large beaker. The impure copper will be used as the positive electrode (anode) and for the negative electrode (cathode) will be a bar of pure copper.
When the electric current is switched on, the bar of pure copper which is the cathode increases greatly in size as copper ions leave the anode of impure copper and attach to the cathode. The anode becomes smaller and smaller as it loses copper ions until all that is left of it is impurities in form of a sludge beneath it.