atomic theory + periodic table

atomic #

the number of protons in an atom

mass #

protons + neutrons

ion

the charge of an atom (can be negative or positive)

isotope

variations of atoms of the same element but the only difference is are the number of neutrons (and their mass)

atomic mass

an average of all isotopes’s weights of an element

formula for atomic mass

(mass A x % of mass A) + (mass B x % of mass B)…

chemical reaction

something that happens when one or more substances change into a new substance through an exchange of electrons

electrons

a subatomic particle with a negative charge that has almost no mass

nuclear reaction

something that happens when a substance changes into a new substance through a change in the nucleus of an atom

nucleus

the center of an atom containing both protons and neutrons (as well as most of their mass)

radioactive

an unstable ion/atom that spontaneously emits small high energy particles

spontaneously

something that occurs naturally without the need for continuous input of external energy

unstable

when an atom or ion doesn’t have 8 valence electrons

radioactive decay

a process that occurs to create a stable atom, usually a different element like alpha particle, beta particle, positron, and gamma rays

alpha particle

an addition of 4 mass and 2 protons so 4/2He added to an equation

beta particle

an electron is added so no mass but one -1 charge (BALANCE THE EQUATION) so 0/-1e is added

positron

0/1 is added so no mass but 1 proton is added (BALANCE THE EQUATION)

gamma ray

no mass or protons added just very high energy

bombardment

hitting particles with other particles at high speeds (particle accelerator)

fission

breaking apart a large radioactive nucleus into nuclei which creates energy (this is what happens in nuclear power plants)

fusion

combining 2 small nuclei to make 1 big one that creates more energy that fission but a lot more mass is lost in this process

4 types of radiation

alpha particle (4/2He), beta particle (0/-1e), positron (0/1)e, gamma ray (0/0weird symbol)

atom

basic unit of an element

john dalton

created the “billiard ball model” and came up with the conclusion that the atom has nothing in it and in indivisible and indestructible which is untrue (as later proven by others)

compounds

a thing made of 2 or more separate elements (basically a mixture)

JJ thomson

created the “plum pudding model” and found out electrons exist. he also says that the atom have a positive charge (but doesn’t know that much about it)

robert millikan

he found out the mass and charge of electrons

ernest rutherford

ran the “gold foil experiment” in which he discovered the nucleus so he believed the atom had tons of empty space, one positive nucleus in the center and atoms around it, and the nucleus is small and very dense

james chadwick

discovered the neutron by bombarding beryllium atoms with alpha particles

niels bohr

created the “planetary model” which shows that electrons orbit the nucleus like how planets orbit the sun

democritus

the first ever to mention the atom (400 B.C.)

electromagnetic radiation

all the energy that travels as waves through space like phone signals and such

wavelength

the distance between crest to crest or trough to trough measured in meters (m) or nanometers (nm)

frequency

the amount of times the wavelength passes a certain point in 1 second

electromagnetic spectrum

all the type of waves so radio waves, microwaves, infrared waves, ROYGBIV (visible waves), UV rays, x-rays, and gamma rays

photon

the type of energy that an electron absorbs and emits as it jumps from ground state to excited state and back down which as it is emitted we see the light as a color

atomic emission spectrum

a black box which only shows certain colors per element so each element has its own unique atomic emission spectrum which can be used to identify that element

relationship between frequency and wavelength

they’re opposites so frequency is high but wavelength is low and the opposite of that

radiowaves, microwaves, and infared lights are ____

less dangerous, bigger wavelengths, less energy, less frequency

UV rays, x-rays, and gamma rays are _____

more dangerous, smaller wavelengths, higher energy, higher frequency

roygbiv is ____

the visible light that’s in the middle of the electromagnetic spectrum

the relationship between gap an electron jumps with the color we see is _____

higher the gap means more energy meaning cooler color like blue or purple and the opposite so smaller gap means less energy meaning a warmer color is produced like red or orange

steps of heat causing us to see color

1- heat causes the electron at ground state to start getting excited 2- electron travels up to excited state and absorbs energy in the form of a photon 3- electron travels back down to ground state which releasing the photon causing energy to be released that we see as color

mendeleev

the arranger of the periodic table

period

a row on the periodic table

group/family

a column on the periodic table

alkali metals

group 1, soft, shiny, good conductors (because high melting point), pretty eager to get rid of 1 electron to become stable also VERY reactive with water

alkali earth metals

same properties as alkali metals but way less reactive

halogens

group 17 that is basically the opposite of alkali metals

nobel gases

group 18, stable, no electronegativity, the group with the highest IE and also the opposite of alkali metals

rare earth metals

located at the bottom of the periodic table (the f block)

metals

located on the left of the stairs. good conductors because high melting points, shiny, and soft, ductile, malleable

metalloids/semimetals

they have both traits of metals and nonmetals

nonmetals

opposite of metals (bad conductors bc low melting point), not ductile, and not malleable

heisenburg uncertainty principle

it’s impossible to know both the velocity and period of the electron at the same time

schrodinger’s model

electrons don’t orbit the nucleus like bohr’s model but instead move in specific regions of space

s-orbital

this is a “spherical shape”, 1 shape, 1 “orientation in space”,1 orbital/sublevel

p-orbital

this is a “dumbbell shape”, 3 shapes, 3 “orientations in space”, 3 orbitals/sublevels

d-orbital

this is a “four-leaf clover” or “dumbbell with a donut”, 5 shapes, 5 “orientations in space”, 5 orbitals/sublevels

f-orbital

there is no name to this but there are various shapes, 7 shapes, 7 “orientations in space”, 7 orbitals/sublevels

describing electrons

in 4p^5: 4 is the energy level, p is the region they’re in (but we dk their position), 4p is the sublevel, 5 is the number of electrons in the 4p sublevel.

aufbau principle

you need to fill the lowest energy level before moving on in order

pauli exclusion principle

there can only be 2 electrons per orbital and they must be facing the opposite direction

hund’s rule

each orbital in a sublevel must all have one electron before doubling up

valence electrons

the outermost electrons (the ones in the highest energy level)

electron shielding

the inner rings with electrons that kinda shield other attractions so it lowers the attraction increasing ionization energy

atomic radius + trend

it’s the space between the nucleus and the valence electrons and on the periodic table it increases as you go down diagonally toward the bottom left corner

ionization energy + trend

it’s the amount of energy needed to remove an electron from a stable atom and on the periodic table it increases as you go up diagonally toward the top right corner.

electronegativity + trend

electronegativity is the strength an element has to “steal” electrons from atoms of other elements and on the periodic table it increases as you go up diagonally toward the top right corner.