Chapter 4 Test Flashcards
Atomic mass
The mass of a single, specific isotope of an atom
Atomic weight
The average of all the naturally occurring isotopes of an element
Isotope notation
A way to easily identify an isotope
Why does mass number tell us? Where is it?
Protons + neutrons
It on the top
What does the atomic number tell you? Where is it?
Protons
Bottom
What happens if you change the number of protons?
You have a different element
Democritus
Theorized that atoms exist
J.J Thompson
Discovered electrons; plum pudding model
Earnest Rutherford
Nuclear model, discovered nucleus and alpha bata particles, later discovered protons
Neils Bohr
Bohr model and planetary model of the atom
Law of definite proportion
Every compound is formed of elements combined in specific ratios by mass that are unique for that compound
Law of multiple proportions
A fixed amount of one element can combine with different masses of a second element and those masses always occur in a ratio that can be reduced to small, whole numbers
Isotope
Atoms with the same number of protons but different number of neutrons
