Since the atomic mass is an average of the masses of all isotopes of that element, you have to consider which isotope is most abundant. In this case, the atomic mass is closest to twelve, so the most abundant isotope of carbon is Carbon 12.
A decomposition reaction.
Answer: Option (d) is the correct answer.
Explanation:
According to Bronsted-Lowry an acid is defined as the specie which is able to donate hydrogen ions when dissolved in water.
For example, 
On the other hand, bases are the species which are able to donate hydroxide ions when dissolved in water.
For example, 
Thus, we can conclude that a definition of an acid is that it donates H ions when dissolved in water.
Answer:
C
Explanation:
When fossil fuels are burned, they release large amounts of carbon dioxide, a greenhouse gas, into the air.
Answer:
option A
Explanation:
because acid comes from preparation of fossil fuel