Question

the compound $\ce{co_{2}}$ is made of
two atoms of cobalt.
one atom of cobalt and two atoms of oxygen.
two atoms of carbon and one atom of oxygen.
one atom of carbon and two atoms of oxygen.

Explanation:

To determine the composition of \( \text{CO}_2 \), we analyze the chemical formula. In a chemical formula, the symbol represents the element, and the subscript (the number after the symbol) indicates the number of atoms of that element. For \( \text{CO}_2 \), "C" is the symbol for carbon, and since there is no subscript next to "C", it means there is 1 atom of carbon. "O" is the symbol for oxygen, and the subscript "2" next to "O" means there are 2 atoms of oxygen. So we eliminate the options related to cobalt (as \( \text{CO}_2 \) has carbon, not cobalt) and the options with incorrect atom counts for carbon and oxygen.

Answer:

D. one atom of carbon and two atoms of oxygen.