1. I. Atomic Structures & Symbols A. Each element has a name and a symbol. –Six carbon atoms are 6 C –A carbon molecule with six carbons is C 6 –Atomic number is always in the LOWER LEFT 6 C –Atomic mass number is always in the UPPER LEFT 12 C, 13 C, 14 C –Both mass number and atomic number may be written with an element – 12 6 C – as we have already seen

2. B. Atomic Structure 1. An atom has an atomic number. This tells you how many protons, neutrons, and electrons that a stable atom has. Ex: Carbon #6 6 P+, 6 N, 6 e-

3. 2. The nucleus and mass number a. The nucleus contains two subatomic particles, the Proton and Neutron. b. The mass number is the number of protons plus the number of neutrons. Ex: (P + N) Carbon has 6 P and 6 N Therefore Carbon's Mass Number is 12.

4. II. Unstable atoms A. Isotopes are atoms of the same element with a different number of neutrons. Ex: Carbon-12 6 P+ and 6 N Carbon-14 6 P+ and 8 N

5. Isotopes of Carbon

6. B. Radioisotopes 1. Radioisotopes are atoms that have unstable nuclear configurations. a. Some elements have no stable isotopes (Technetium – the first element to be artificially produced) b. Some elements have several stable isotopes (Lead) c. Some elements only have one stable isotope (Beryllium)

7. C. Ions are atoms with a different number of electrons 1. Anions are atoms that have gained electrons. They have a negative charge. 2. Cations are atoms that have lost electrons. They have a positive charge.

8. D. Atomic Mass A. Atomic mass the average mass of all of the existing isotopes of an element. For instance, you would calculate the average of all of the C-12, C- 13, and C-14 atoms.

9. E. Coulomb’s Law 1. The closer 2 objects are the stronger the forces between them. a. Like charges repels, opposites attract b. If you Increase the distance, you decrease the attraction c. If you decrease the distance, the attraction increases in a 1:2 ratio

10. Coulomb continued 1. You can’t have an atom with just protons due to repulsion forces a. Neutrons in the nucleus create a buffer b. The atom's strong force helps to overcome this.

11. III. Electron Configurations: Electrons and Light  There is very little mass in an e -  Most of the atom’s volume determines almost all of its chemistry.  We study the light that electrons emit and their wavelengths.

12. A. Electromagnetic Waves 1. The visible spectrum is only a tiny part of the electromagnetic spectrum  – rays, x-rays, uv, visible, infrared, micorwaves, radiowaves. b. Characteristics: speed, wavelength, frequency i. Move slower though matter than through space ii. 2.998 x 10 8 m/s = c = speed of light iii. At this speed it takes light 8.33 minutes to travel from the sun to the earth.

13. Electromagnetic Waves

14. B. Wave Structure 1. The distance between 2 peaks or 2 troughs is considered 1 wavelength a. This is measured in meters  rays are the shortest – 10 -13 m c. Radio waves the longest – 10 5 m

16. C. Wave Frequency 1. The frequency of a wave is how long a wave takes to move past a stationary point in 1 second. a. One wave per second is a hertz (Hz). b. Frequencies range from 1000Hz to 10 22 Hz http://id.mind.net/~zona/mstm/physics/waves/partsOfAWave/waveParts.htm

17. D. Simple relationship between wavelength, speed and frequency of electromagnetic waves: Frequency x wavelength = speed of light What is the frequency of a red light if it has a wavelength of 7.6 x 10 -7 m?