Atom unit Flashcards
Five models of atoms
Dalton
Thomson
Rutherford
Bohrs
Schrodingers
Dalton
All elements are made of atoms
Elements have whole number ratios
Thomson
Atoms contain equal amounts of positive and negative charge
Rutherford
Positive dense nucleus and negative electrons circling
Bohrs
Electrons orbit the nucleus in specific levels of energy
Schrodingers
Electrons are in probability zones and locations cannon be pinpointed
Atoms are particles and waves at the same time
Quarks
The building blocks of protons and neutrons
Protons are made up of
2 up quarks and 1 down quark
Neutrons are made up of
2 down quarks and 1up quark
Down quark
-1/3
Up quark
2/3
Gluons
The “glue” that holds quarks together
Earliest designer of the periodic table
Dimitri Mendeleev
Periodic
A regular repeating pattern
Isotopes
Atoms with different numbers of neutrons
Four ways to write an isotope
Nickel
Ni61
Ni-61
28-Ni-61
61
Ni
28
Ions
Versions of an element that have lost or gained electrons on their valence shell
Why do atoms become ions
So they can have a complete valence shell
Cation
Positive ion
More protons
What type of elements become cations
Metals on the left side of the table
Anion
A negative ion
More electrons
What type of elements become anions
Non-metals on the right of the periodic table
Charge on ions that form group 1
+1
Charge on group 2
+2
Charge on group 13
+3
Charge on group 15
-3
Charge on group 16
-2
Charge on group 17
-1
Group 18
They already have a full valence shell (Nobel gases)
Atomic radii trend
Atoms decrease in radius as it moves left to right across a period
Atoms decrease in radius as it moves up a group
Ionization energy trend
Left to right across a period electrons are more difficult to remove
Bottom to top of a group electrons are more difficult to remove
