science

1. Combinations of symbols that show the elements present in a compound and the ratio of their atoms (e.g., H2O for water).
5. Small units that make up matter.
9. Notation that indicates the type and number of atoms present in a molecule of a substance.
10. Identifying or acknowledging the existence of something.
12. Substances composed of two or more elements or compounds physically mixed together but not chemically combined.
13. Substances that consist of only one type of atom, which cannot be broken down into simpler substances.

2. How particles are organized or positioned relative to one another in a substance.
3. Displayed or depicted in a specific way.
4. Providing information or reasons to clarify a concept.
6. Representations used to stand for elements (e.g., H for hydrogen).
7. Substances composed of two or more elements chemically combined in a fixed ratio.
8. Representing or showing a system using diagrams, visuals, or other methods.
11. Relating to substances and processes involved in chemistry.