atoms protons and neutrons
What is an atomic number?
The number located at the top of an element on the periodic table also is the number of protons and electrons.
What is a valence number?
The number of electrons on the outer shell
atomic structure
subatomic particles
neutrons: symbol, charge, mass, location, purpose
symbol: No, charge: neutral (none), mass: 1 AMU location: nucleus, purpose: stabilizes atom by neutralizing the "strong force" surrounding protons (which repel them from one another)
protons: symbol, charge, mass, location, equals, purpose
symbol: P+1, charge: positive, mass: 1 AMU, location: nucleus, equals: # electrons (in neutral), purpose: determines, atomic#
electrons: symbol, charge, mass, location, equals, purpose
symbol: e-1, charge: negative, mass: 0 AMU location: outside nucleus, in electron cloud, in shells/rings, equals: # protons (in neutral), purpose: cancels out positive charge of protons AND creates chemical bonds
How do you determine the number of protons, electrons, and neutrons?
The atomic number is the number of protons and electrons. To find neutrons take atomic number minus the atomic mass.
What is an atom?
The building blocks of matter
What is an oxidation number?
a charge that the atom has become
element set up
atomic #: bottom left, atomic mass: top left, top right: top
numbers neutrons
atomic mass - protons = neutrons
amu
atomic mass unit
AMU
atomic mass units
first letter or two of element name
atomic symbol
What is the Greek word for atom?
atoms meaning "not able to be divided."
valence electrons create ___
bonds
What is the Octet Rule?
Means the atoms are happy or stable with 8 electrons on the outer shell. The exception is that the first orbital can hold 2.
Anion
Negatively charged ions where electrons have been gained ie: N^3- (gained 3 electrons)
What is a neutron?
Neutral charge and is also located in the nucleus.
atomic number
Number of protons/electrons
atomic mass
Number particles in nucleus (protons & neutrons) can be altered when # of neutrons changes, making it an isotope
Cation
Positively charged ions where electrons have been lost ie: Ca^2+ (lost 2 electrons)
What is atomic mass?
Protons and neutrons.
pure substance
Pure substances are defined as substances that are made of only one type of atom or molecule.
atom percentages
99.99% empty space nucleus = .001% of atom, but 99.9% of total mass (small but dense)
Ion
A charged ion where electrons have either been gained or lost
nuclear decay
A process that occurs when an unstable atomic nucleus changes into another more stable nucleus by emitting radiation.
radioactive
Any element that spontaneously emits radiation.
Atoms
Atoms are extremely small and can't be seen with the naked eye
How do you determine the number of electrons that are given or taken be an atom?
Depending on the covalent bond and how the electrons are shared between it.
Frequency
How often it occurs naturally
What is an electron?
Located on the outside of the nucleus known as the outer shell and has a negative charge that determines what type of change it has.
What is a proton?
They determine the element and it is positively charged and located in the nucleus.
outermost shell should contain ___ electrons
eight
chemical behavior is due to
electrons
protons =
electrons
electron shells
first shell: 2, second shell: 8, third shell: 8
atomic weight
isotope weight
structure of atoms
isotopes
electrons
negative charge
neutrons
neutral charge
mass number atomic number =
neutrons
atomic number
numbers of protons
outermost shell is filled; considered stable
octet rule
neutron weight
one amu
proton weight
one amu
quarks
particles that make up protons and neutrons protons: 2/3 + 2/3 -1/3 = 1 (AMU) neutrons: 2/3 - 1/3 -1/3 = 0 (AMU)
protons
positive charge
mass numbers
protons+neutrons
outermost electrons
valence electrons
electron weight
zero amu
