science protons

what most accurately represents john dalton's model of the atom

a tiny solid sphere w/ a predictable mass for a given element

what is true about subatomic particles

an electron has far less mass than either proton or neutron

the region in which an electrons is most likely to be found is called

an orbital

the greek philosopher democritus coined what word for a tiny price of matter that cant be divided

atom

the number of protons in one atom of an element is that elements

atomic number

To find the number of neutrons in an atom, you would subtract

atomic number from mass number

unlike democritus, Aristotle didn't believe that matter was composed of tiny, indivisible

atoms

the moving blades of an airplane propeller provide an analogy for the electron _____

cloud

john dalton observed that elements always combine in the same ratio to form a particular _____

compound

In an atomic model that includes a nucleus, positive charge is

concentrated in the center of an atom

thomsons experiments provided evidence that an atom

contains negatively charged particles

Which subatomic particle has a negative charge?

electron

In Bohr's model of the atom, ______ move in fixed orbits around the sun

electrons

when an atom gains or lose energy some of its ____ may move between energy levels

electrons

an atom in which an electron has moved to a higher energy level is a ____ state

excited

when all the electrons in an atom are in orbitals w/ the lowest possible energy the atomic is in its ____ state

ground

Rutherford model of the atom

it is a huge stadium with a positively charged marble at the center

In Niels Bohr's model of the atom, electrons move

like planets orbiting the sun

the ____ of an isotope is the sum of the number of protons and neutrons in its nucleus

mass #

the subatomic particles that JJ thomson discovered has a ____ charge

negative

protons and ___ are found in the nucleus of an atom

neutrons

the nuclei of isotope contain different numbers of

neutrons

If element Q has 11 protons, its atomic ____________________ is 11.

number

Neutrons and ____________________ have almost the same mass.

protons

what is not true about subatomic particles is NOT true

protons and neutrons have the same charge

what can you assume has happened if an electron moves to a higher energy level

the electron has gained energy

what is unique for any given element

the number of protons

what is true about oxygen-18 and oxygen-19

they are isotopes of oxygen