Answer: Hey again!
Option (a) is the correct answer.
Explanation:
Elemental form of carbon means the pure form of carbon, that is, carbon is present in its natural form.
An elemental form also means that the pure atoms are not attached to any other atom.
For example, diamond is an allotrope of carbon in which there are only carbon atoms attached to each other and no other atom is present in it.
Whereas methane has carbon and hydrogen atoms attached to each other therefore, it is not an elemental carbon. And proteins include different atoms attached to each other.
Thus, we can conclude that diamond is an example of elemental carbon.
Explanation:
Answer:

Explanation:
Hello,
In this case, the pH is computed by:
![pH=-log([H^+])](https://tex.z-dn.net/?f=pH%3D-log%28%5BH%5E%2B%5D%29)
Whereas the concentration of hydrogen ions equals the concentration of the acid for strong acids such as hydrochloric acid (HCl) due to its complete ionization in solution, which means that such concentration is 0.00125 M. Thus, the pH turns out:

Regards.
78% is nitrogen, 21% is oxygen, 1% is other.