Answer:
1st Blank: <em>1 Co</em>
2nd Blank:<em> 2 Na2S</em>
3rd Blank:<em> 4 Na</em>
4th Blank:<em> 1 CoS2</em>
Explanation:
<em>Trust me</em>
The right answer is 2.
The number of protons contained in a nucleus (called an atomic number) is characteristic of a chemical element. For a given atomic number, the number of neutrons defines different "types" of this element: isotopes. The variation of the number of protons of the nucleus of an atom, during a nuclear reaction for example, causes a change of the element studied.
Answer: water
Explanation:if you look at a globe most of it is blue and blue on a globe is water so that means water covers most of the earth