science ch 7
neutron charge
0
proton charge
1+
electron charge
1-
neutron smaller parts
2 down and 1 up quark
if an ion contains 10 electrons, 12 protons, and 13 neutrons, what is the ions charge?
2+
how many neutrons does iron-59 have?
33
atom size
7.5 trillion can fit into a period
electron
A particle with one negative charge
electron cloud
Area an atomic nucleus where an electron is most likely to be located
isotopes
Atoms of the same element that have different numbers of neutrons
average atomic mass
Element is the average mass of the elements isotopes weighted according to the abundance of each isotope
atomic number
Number of protons in an atom of an element
atom
The smallest piece of an element that still represents that element
ion
atom that is no longer neutral because it has gained or lost electrons
proton
atomic particle that has one positive charge
atom location
between atoms
which part of an atom makes up most of its volume?
electron cloud
modern atomic model location of electron
electrons for the electron cloud and move around the nucleaus
bohr atomic model location of electrons
electrons move around the nucleaus in circular orbits at different energy levels
radioactive
elements that spontaneously emit radiation
proton smaller parts
made of 2 down and 1 up quark
nucleus
most of the atom's mass and positive charge is concentrated in a small area in the center of the atom
nutron
neutral particle that exist in the nucleus of an atom
electron smaller parts
no small particles
mass number
of an atom is the sum of the number of protons and neutrons in an atom
Democritus
people disagreed with his ideas about matter; 2000 years later people started studying it
nuclear delay
process that occurs when an unstable atomic nucleus changes into another more stable nucleus by emitting radiation
nucleus smaller parts
protons and neutrons
how can radioactivity help humans?
radiation therapy is beneficial to humans by destroying cancer cells and other harmful cells
Aristotle
said that all matter is made up of: fire, water, air, and earth; people agreed but he was wrong
atoms are made of
smaller particles
what did Democritus believe an atom was?
solid, indivisible object
which determines the identity of an element?
the number of its protons
what was happening to the cathode rays?
they are attracted to the negative plate
why was rutherford's students surprised by the results of the gold foil experiment?
they didn't expect the alpha particles to bounce bakc from the foil
6 types of quarks
up, down, charm, strange, top, bottom
atomic number determines
what element someone's using
