Some substances are not composed of molecules. Instead, these substances are composed of atoms arranged in a crystal structure, or repeating pattern. Models that represent these substances show this repeating pattern of atoms.

Question

The chemical formula for a substance with a crystal structure shows two things. It shows which chemical elements the substance is composed of. It also shows the ratio, or relative amounts, of the chemical elements in the substance. For example, the chemical formula for beryllium fluoride,
BeF2
, shows that there is one beryllium atom for every two fluorine atoms.
Select the model that represents the substance with the chemical formula
FeS2
.

B

N

S

Fe

Ga

As

Answer 1

The chemical formula FeS2 indicates that the substance is composed of one iron (Fe) atom and two sulfur (S) atoms. To determine which model represents this substance, you would look for a structure that includes one iron atom and a repeating pattern that shows two sulfur atoms associated with it.

Please review the models you've referenced (B, N, S, Fe, Ga, As) in the context of how they might represent the arrangement of Fe and S atoms in FeS2. The model that best represents one iron atom bonded to two sulfur atoms should be selected. If you need further assistance, please provide additional context or descriptions of the models available for selection.