- How do we know that air is not a single substance?
- Metals have many similar properties, but not all properties are shared by all metals. Why is it useful to group them as metals?
- Why is it important that the Periodic Table is structured as a table, rather than a list of elements?
- How is the Periodic Table important for all of science and not just chemistry?
Requirements: explicit

Leave a Reply
You must be logged in to post a comment.