I have no formula however the process would be erosion... copper is a type of metal and when it rots from water or any type of liquid damage it erodes and gets that green coat.
Yes if we use the resource up before it can renew itself then it could be used up and be depleted or near depletion. The resource has to have time to come back and if we use it up to fast then the resource can not take the time it needs to come back.
Answer: a. BaO
Explanation:
For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.
Here element barium is having an oxidation state of +2 called as
cation and
is an anion with oxidation state of -2. Thus they combine and their oxidation states are exchanged and written in simplest whole number ratios to give neutral 
Answer:

Explanation:
Hello,
In this case, we can consider the following chemical reaction for the oxidation of copper which only occurs at high temperatures:

In such a way, for 0.032 grams of copper, the following grams of copper (II) oxide (black product) are yielded:

Therefore, the percent yield is:

Best regards.
If your findings disproves your hypothesis then your hypothesis is probably wrong.