Final answer:
The simplest molecular formula for a molecule with one carbon atom and two oxygen atoms is CO₂, commonly known as carbon dioxide.
Step-by-step explanation:
The simplest formula for a molecule containing one carbon atom and two oxygen atoms is CO₂. The elements should be listed in the order given, so we start with carbon (C) and then add oxygen (O). Since there are two oxygen atoms, we include the subscript '2' after the oxygen symbol to indicate this, making the formula CO₂. This molecule is also known as carbon dioxide, which is well-known for its role in the Earth's atmosphere and in the process of cellular respiration.