1. The Atom
Ch.17 Sec.1

2. Atom
Contain a nucleus, protons, neutrons, and electrons

3. Nucleus Center of atom Positive (+) charge
Contains protons and neutrons

4. Protons (p+) Protons = Positive Charge (1+) Relative Mass: Actual Mass
= 1 (compared to other subatomic particles)
Actual Mass
= x 10-24
Location = nucleus
Number of protons varies w/ ea. element

5. Neutrons (no) Neutrons = Neutral Charge (none or zero) Relative Mass
= 1
Same as proton
Actual Mass
= x 10-24
Location = nucleus

6. Electrons (e-) Electron = Negative charge (1-) Relative Mass
= 1/1836
Actual Mass
= 9.11 x 10-28
Location = electron clouds or orbits
Constantly move around nucleus

7. Atoms Are Neutral # of Protons (+) = # of Electrons (-)
Neutrons do not matter because they do not have a charge
Ex: Helium:
2 P - (+2)
2 N - (0)
2 E - (-2)
0 overall charge

8. Neutral Atom 3 Protons (+3) 4 Neutrons (0) 3 Electrons (-3)
= 0 overall charge

9. Changing Particle #s Cannot change p+ # (diff. element)
n0 can change (neutral don’t matter)
Isotope
E- # can change
Lose, gain share e- when bonding