People
John Dalton
Elements are composed of tiny indestructible particles called atoms.
What are the 3 parts of the nuclear theory?
Most mass and all protons are in the core called the nucleus.
Most of atom is empty space where electrons are dispersed.
Equal amount of electrons outside of the nucleus to protons inside the nucleus so atoms are neutral-charge.
What are items on the periodic table classified as?
metals, mettaloids, nonmetals
According to Dalton’s atomic theory, atoms of the same element have:
The same properties and mass
Who was Democritus?
guy who first discovered atoms
What was rutherford's experiment called?
the gold foil experiment
What was JJ Thomson's Experiment?
The Plum Pudding experiment
What are positively and negatively charged ions called?
cations, anions
Dmitri Mendeleev is known for:
creating the original periodic table
What did JJ Thomson do?
discovered the electron
What are the combined masses of protons and neutrons expressed as?
atomic mass
What did JJ Thomson theorize about the atom?
there was a sphere of positive charge around the atom
What are isotopes?
atoms with the same # of protons but different number of neutrons
Who was Leucippus
some irrelevant guy who kinda helped democritus
sidekick
What did Marie Curie do?
What are main group elements and transition elements labelled with?
letters "A" and "B"
What determines a element's atomic number?
# of protons
Name all the groups in the periodic table.
Akali Metals, Noble Gases, Alkaline Earth Metals, Halogens
What is most of an atom composed of?
empty space
What did Ernest Rutherford do?
created nuclear theory of the atom
What are the properties of metals, nonmetals, and metalloids?
Metals:on the left and conduct heat or electricity well
Nonmetals:on the upper right and usually do not conduct heat or electricity well
Metalloids:have mixed properties and are also called “semiconductors” because they only conduct under certain situations (useful for electronic devices)
What are the 3 subatomic particles, what are their names, what are their charges, and where are they located?
Proton - (+) in nucleus
Neutron - (neutral) in nucleus
Electron - (-) orbiting nucleus
What happens to an atom when they lose or gain an electron? What do they become
an ion
What are the properties of all the groups of elements?
Akali Metals, Noble Gases, Alkaline Earth Metals, Halogens
Alkali Metals:Very reactive metals (far left side)
Noble Gases:Nonreactive gases (far right side)
Alkaline Earth Metals:Very reactive nonmetals (left of noble gases)
Halogens:Very reactive nonmetals (left of noble gases)Metals, nonmetals, transition metals, metalloids