Explanation:
Calcium carbonate (Chalk) is a chemical compound, with the chemical formula CaCO3. Calcium carbonate (Chalk) is a chemical compound, with the chemical formula CaCO3.
I think it is B. That is the most reasonable answer....
Answer:
<h3><em>Seventeen elements are generally classified as nonmetals; most are gases (hydrogen, helium, nitrogen, oxygen, fluorine, neon, chlorine, argon, krypton, xenon and radon); one is a liquid (bromine); and a few are solids (carbon, phosphorus, sulfur, selenium, and iodine).</em></h3>
The first answer; Nickel has an atomic number of 28 (28 protons). and cobalt has an atomic number of 27 (27 protons).
