If yellow spheres represent sulfur atoms and red spheres represent oxygen atoms, which of the following drawings shows a collection of sulfur dioxide (SO₂) units?
(a)
(b)
(c)
(d)

Verified step by step guidance

1. Identify the chemical formula for sulfur dioxide, which is SO₂. This indicates each molecule consists of one sulfur atom and two oxygen atoms.
2. Examine each drawing to count the number of yellow spheres (sulfur atoms) and red spheres (oxygen atoms) grouped together that represent a molecule.
3. Match the groups of atoms in the drawings to the chemical formula of sulfur dioxide. Look for groups where there is one yellow sphere and two red spheres closely associated.
4. Ensure that the groups identified in the previous step are isolated units, meaning they are not sharing atoms with other groups or forming larger structures.
5. Select the drawing where the groups of one yellow sphere and two red spheres are consistently and correctly shown, as this represents the sulfur dioxide (SO₂) units.

Key Concepts

Chemical Formula

A chemical formula represents the composition of a compound using symbols for the elements and numerical subscripts to indicate the number of atoms of each element. For sulfur dioxide (SO2), the formula indicates one sulfur atom and two oxygen atoms, which is essential for visualizing the molecular structure.

Molecular Structure

Molecular structure refers to the arrangement of atoms within a molecule, including the bonds between them. In SO2, the sulfur atom is centrally located with two oxygen atoms bonded to it, forming a bent shape due to the repulsion of lone pairs of electrons on the sulfur atom.

Representation of Atoms

In molecular models, different colors or shapes are often used to represent different types of atoms. In this question, yellow spheres represent sulfur atoms and red spheres represent oxygen atoms. Understanding this representation is crucial for correctly identifying the structure of sulfur dioxide among the provided drawings.