discovering parts of an atom

______ was one of rutherfords colleagues

james chadwick

rutherford's students performed an expirement during which they shot _______ particles into a piece of ______

alpha, gold

a ______ is the smallest piece of an element that still represents that element

atom

smallest piece of an element that still represents the element

atom

john dalton proposed the _____ theory which was based on careful observations and _______ of chemical reactions

atomic, measurements

democritus proposed that matter is made of small, indivisible objects called ________

atoms

the atomic model of _____ propsed that _______ move in circular orbits or ________ around the nucleus

bohr, eletrons, energy levels

thomson discovered that the rays in a _______ were attracted to a _____ charged plate which means that the rays have a _______ charge

cathode ray tube,positively, negative

the limitation of bohr's model is that electrons do not actually move in ________ orbits

circular

dalton's theory states that atoms cannot be divided _______ or destroyed

created

many ancient greek philosophers thought that all matter was made of only 4 elements fire, water, air, and ______

earth

atomic particle with one negtive charge (1-)

electron

area around an atomic nucleus where an electron is most likely to be foud

electron cloud

in modern atomic theory electrns form a _______ which is an area around the ________ in which an electron is likely to be located

electron cloud, nucleus

it also stated that atoms of one ______ are different from atoms of other ______

element, element

an electron cloud is mostly_____ space

empty

when energy is added to an atom electrons move higher _______ when energy is released by the electron it moves back to a lower level (when this happens it guves off light)

energy level

rutherfords resulting atomic model propsed that most of an atom's ______ and _____ charge is concentrated in the center of the atom

mass, positive

he proposed that different types of _____ are made from different types of atoms

matter

neutral particle in the nucleus of an atom

neutron

chadwick discoved the __________ a neutral particle that exists in the _____ of an atom

neutron, nucleus

protons and ______ are made of smaller parts called ________

neutrons, quarks

small area in the center of an atom in which most of an atom's mass and positive charge is concentrated

nucleus

the _____ is the small, positively charged area in the center of the atom

nucleus

atomic particle with one postive charge (1+)

proton

in the nucleus is the _____ which is an atomic particle with one positive charge

proton

protons and neutrons are consisted of what quarks

protons- 2 up 1 down neutrons- 2 down 1 up

atoms were first seen by using a _______ microscope

scanning tunneling

the results showed that most of the particles traveled throught he foil but some bounced to the ______ and a few bounced straight back

side

there are _____ types of quarks

six

thomson's atomic model stated that an atom is a positively charged _______ with _______ throughout it

sphere, electrons

these early scientist were not able to ___ their theories

test

what are the 6 types of quarks

up, down, top, bottom, charm, strange