Chapter 3/4 Chem 105

2. a mixture that is visually indistinguishable in parts and does have a uniform composition.
5. _____number, Number of nucleons
6. ___number, The number of protons in the nucleus
11. ex: mixture of sand in water or oil in water
12. Has a negative charge
13. consists of only a single element or a single compoundee,
14. A type of model that replicates an object at a more convenient scale.
15. Center of an atom
16. poor conductors of electricity and heat, neither malleable nor ductile
19. a combination of two or more substances in which each substance retains its properties
22. ex: Air and salt water
24. a property that characterize the ability of a substance to react with other substances or to transform from one substance to another.
26. any material consisting of only one type of atom.
27. an instrument used to observe the color components of any light source.

1. Has the same number of electron shells
3. Share both metal and nonmetal characteristics
4. ex: milk and blood
7. a change where the chemical bonds are changed in a reaction.
8. Has a similar electron configuration
9. characterized as being shiny, opaque, and good conductors of electricity and heat
10. Has a positive charge
17. ___waves that are vibrations of electric and magnetic fields.
18. a property that describes the look or feel of a substance.
19. Determined the charge of an electron with the oil-drop experiment.
20. distance between two crests of an electromagnetic wave
21. Developed the planetary model
23. A type of model that is a representation of a system that helps us predict how the system behaves
25. Has no electric charge