1. Properties of Subatomic Particles
Protons:
Amount of positive charge varies among elements
Proton: ___________ charged, found in _________
charge: 1+
nucleus must contain at least one

2. Properties of Subatomic Particles
Electrons
Detected by ____________
Electron: __________ charged, found _______ nucleus
charge: 1

3. Properties of Subatomic Particles
Neutrons:
1932, James _______________
Concluded:
Neutral because a charged object didn’t cause ________________
Neutron: ____________particle, found in ____________
Mass almost exactly equal to a ____________’s

4. Comparing Subatomic Particles
How particles behave
No instrument shows the inside of an atom
Using Mass, Charge, and Location

5. Atomic Number: Atomic Number and Mass Number
Number of ___________ in an atom of that element
All atoms an element have the same atomic number
Each element has a unique atomic number
Atoms are ______________
Atomic number also equals the number of _______ in an atom of that element.

6. Atomic Number and Mass Number
Examples:
A The atomic number of sulfur (S) is 16.
B The atomic number of iron (Fe) is 26.
C The atomic number of silver (Ag) is 47.

7. Atomic Number and Mass Number
________ of the protons and neutrons
To find the number of neutrons, you need:
mass number
atomic number

8. Isotopes Atoms of the same element that have
different numbers of _________________
different __________ numbers
Named by _____________ numbers
Example:
oxygen has 3 isotopes: oxygen-16, oxygen-17, oxygen-18
all three can react with hydrogen to form water or with iron to form rust

9. Isotopes Hydrogen isotopes are an exception:
noticeably different __________________
Hydrogen-1 (Almost all hydrogen), Hydrogen-2, Hydrogen-3
Hydrogen-1 has one proton, so adding a neutron doubles its mass
____________________: contains hydrogen-2 in place of hydrogen-1