Unit 1 Flashcards
Particle theory of matter
John Dalton
1) All matter is made up of particles
2) Atoms can’t be broken down further
3) Atoms can be rearranged with each other
4) Atoms of the same element are the same
Valance shell
Outermost shell, only electrons that can change
Atomic number
Number of protons and electrons
Atomic mass
Total mass of protons and neutrons. Atomic mass- atomic number = number of neutrons
Octet rule
Atom is most stable with a full shell of electrons
Ions
Atoms that become charged through chemical bond s
Anion
Negative, gains electrons. Non metals
Cations
Positive, looses electrons. Metals
Isotopes
A form of an element where the number of protons stays the same but the number of neutrons changes
Isotopic abundance
What % of an isotope exists. Average atomic mass= (iso1)x+ (iso2)(1-x)
Periodic law
If they are in the same column, they react the same because they have the same number of valence electrons. The further down you go, the more reactive you get
Necular strength
The more protons, the greater the charge and make the atomic radio smaller because they draw electrons in
Ionization energy
The amount of energy required to pull electrons away from an element
Electron affinity
Energy change when a neutral atom gains an electron
Electronegativity differences
The amount of energy required to pull electrons away from other atoms