Matter Review

2. discovered electrons
4. change/ a change in size, shape, form, or state of matter in which the identity stays the same
6. the ability of one substance to dissolve in another
7. atomic mass/ the average mass of an element's isotopes, weighted according to the abundance of each isotope
11. the process that occurs when an unstable atomic nucleus changes into another more stable nucleus by emitting radiation
14. states that electrons can be found in the electron cloud
16. any of two or more atoms of the same element that have different numbers of neutrons
20. Said, "Atoms are small solid objects that cannot be divided, created, or destroyed"
22. the number of protons in an atom
24. to form a solution by mixing evenly
25. the mass per unit volume of a substance

1. the sum of protons and neutrons
3. anything that has mass and takes up space
4. a characteristic of matter that you can observe or measure without changing the identity of the matter
5. states that electrons orbit the nucleus
8. the smallest piece of an element that still represents the element
9. mixture/ a type of mixture that is unevenly mixed
10. a characteristic of matter that can be observed as it changes to a different type of matter
12. a type of mixture that is evenly mixed
13. a change in matter in which the substances that make up the matter change into other substances with new physical and chemical properties
15. discovered the nucleus
17. describes elements that spontaneously emit radiation
18. a substance that consists of two ore more different elements chemically bonded together
19. matter with a composition that is always the same
21. credited with discovering neutrons and that they are neutral
23. an atom that is no longer neutral because it has gained or lost electrons