The model<span> of the </span>atom<span> has dramatically </span>changed<span> over many many years.We learn </span>atoms<span> make up different substances and are the smallest particles of matter. which can have subatomic particles that are very small portions of matter.at first scientist only thought there were electrons which are negatively charged.</span>
In what meters? miles an hour? i can’t answer unless i know that
Mixture/ compound
hope this helps
Answer:atomic mass, neutrons in the nucleus
Explanation: because I remember from when I took honors chemistry last year we learned about this and it’s called the atomic mass when looking at an atom and the neutrons in the nucleus are effected by it.
Answer:
The chemical elements are arranged in order of increasing atomic number.
Explanation:
Hydrogen = 1
Helium = 2
Lithium = 3