Question

select all the ways in which two substances can be different
two substances can be composed of the same chemical elements, but the substances can have crystal structures with atoms that are arranged differently.
two substances can be composed of different chemical elements.
two substances can be composed of molecules that contain the same chemical elements but have different numbers of atoms of each element

Explanation:

1. First option: Substances with the same elements can have different crystal structures (e.g., diamond and graphite from carbon), making them different. This is valid.
2. Second option: Different chemical elements will inherently make substances different (e.g., water - H₂O vs. carbon dioxide - CO₂). This is valid.
3. Third option: Molecules with the same elements but different atom counts (e.g., CO and CO₂) are different substances. This is valid.

All three options describe valid ways two substances can differ.

Answer:

All three options (the ones stating "Two substances can be composed of the same chemical elements, but the substances can have crystal structures with atoms that are arranged differently", "Two substances can be composed of different chemical elements", and "Two substances can be composed of molecules that contain the same chemical elements but have different numbers of atoms of each element") are correct.