Label the following species as molecules or ions. (c) NO₂

Verified step by step guidance

1. Step 1: Understand the difference between molecules and ions. A molecule is a group of two or more atoms held together by chemical bonds. An ion, on the other hand, is an atom or molecule that has gained or lost one or more electrons, giving it a net positive or negative charge.
2. Step 2: Look at the given species, NO₂. This is a combination of nitrogen and oxygen atoms.
3. Step 3: Check if there is any charge associated with the species. If there is no charge, it is a molecule. If there is a charge, it is an ion.
4. Step 4: In this case, NO₂ does not have any charge associated with it.
5. Step 5: Therefore, NO₂ is a molecule.

Key Concepts

Molecules

Molecules are neutral entities formed when two or more atoms bond together through covalent bonds. They can consist of the same or different elements and are characterized by their specific molecular structure. For example, a molecule of water (H2O) consists of two hydrogen atoms and one oxygen atom.

Ions

Ions are charged species that result from the loss or gain of electrons by an atom or molecule. When an atom loses electrons, it becomes a positively charged cation, while gaining electrons results in a negatively charged anion. For instance, Na+ is a sodium ion that has lost one electron, while Cl- is a chloride ion that has gained one.

Nitrogen Dioxide (NO2)

Nitrogen dioxide (NO2) is a molecule that consists of one nitrogen atom covalently bonded to two oxygen atoms. It is a neutral species, meaning it does not carry a charge, and is often involved in various chemical reactions, including those related to air pollution and the formation of smog.