Chapter 2 Rad Structure of matter
Atomic Mass
# of nucleons+protons+neutrons
proton
+1
electron
-1, 2000 times smaller charge
Amu of an electron is
0
neutron
0, similar to proton but neutral charge
3.3 half-lives =
1 tenth life
one atomic mass unit is equal to________ the mass of a carbon-12 atom
1/12
neutrons and protons(nucleons) are each nearly________ times ________ of electrons
2000, mass
Maximum electrons per shell is
2n^2 where n is shell number
Maximum electrons per shell
2n^2, n=shell number
What is the atomic number of an atom with 5 protons, seven neutrons, and six electrons?
5
AMU # example
6.989
what are the maximum number of electrons shells possible in an atom?
7
If there is an R shell what us the max # in P shell
72
Maximum # of electrons in the outer shell is
8
The outermost shell of an atom can have a maximum of
8
Electron mass in kilograms
9.1x10^-31
What is the particle called that is made of two protons bound to two neutrons( same as a Helium nucleus)?
Alpha particle
Isobar
Atomic nuclei that has the same atomic mass(nucleons) number but different # of protons(different atomic numbers) and different #of neutrons
Through the process of ionic bonding, two atoms:
Attract
__________ was miniature solar system in which the electrons revolve about the nucleus in prescribed orbits or ____________
Bohr's model, energy levels
his work resulted in the first periodic table of the elements
Dimitri Mendeleev
What fundamental particle gas an atomic mass number of 0?
Electron
Which of the following has the least mass?
Electron
What keeps electrons in the shells of their atoms?
Electron binding energy
Atoms in each of the Periodic Table of the Elements have the same number of
Electron shells
An alpha particle is not an atom because it has no:
Electrons
this is determined by the relative abundance of Isotopes and their respective atomic masses
Elemental Mass
Photons are emitted in:
Gamma rays
Atomic Mass Unit
Is equal to 1/12 the mass of a carbon - 12 atom
Atomic mass( protons+neutrons+electrons)
Is the same as elemental mass
What are atoms called that have the same number if neutrons but different number of protons?
Isotones
What are atoms called that have a different number of neutrons but the same number of protons?
Isotopes
Centrifugal force
Keeps electrons at their distance from the nucleus(flying out from the center force)
in their normal State atoms are electrically _________ , the electric charge of the atom is ___________
Neutral, zero
Group VII
Nobel gases
Beta particle
Occurs more frequently and has mass
the number of __________ plus the number ________ in the nucleus of an atom is called the atomic mass number, symbolizing by A
Protons, neutrons
The atomic mass is measured by the :
Sum of protons, electrons, and neutrons
If you change the # of protons
The element change
radioactivity
The emission of particles and energy in able to become stable
Centripetal force
The force that keeps an electron in orbit and from flying away from the( also called Center seeking Force) because of opposite charges attract
The larger the atom
The higher the binding energy in inner shells
Atomic Number
The number of protons in the nucleus of an atom of an element(Z number)
Isomer
The same atomic number and the same atomic mass number; difference in the nucleon arrangement and resultant different energy states.
radioactive decay
The transformation process of an atom to become another atom through the emission of particles and energy
which of the following is not a fundamental particle?
alpha particle
these particles have for atomic mass units, or positive in charge, and originated from the nucleus of heavy elements
alpha particles
The smallest particle of an element is
atom
a measurable quantity of sodium bicarbonate constitutes a chemical compound commonly called
baking soda
these particles produced through radioactive decay have an atomic mass number of 0 and have a unit of negative charge
beta particle
X-rays
comes from the electron cloud
What are combinations of elements that are bonded together called?
compounds
The two primary bonding that occur when atoms combine into molecules.
covalent and ionic bonding
The process in which two atoms bond by sharing some of the same electrons, which revolve around both nuclei.
covalent bonding
Beta emission
ejected from nucleus and a neutron converts to a proton
the orbit around the nucleus of an atom and has negative electrical charge
electron
the strength of attachment of an electron to the nucleus is called the
electron binding energy
the fundamental particles of an atoms are
electrons protons and neutrons
Ulta's have mass but no charge true or false
false
centrifugal force
flying out of the center
These _________ are emitted from the nucleus of a radiostotope and are usually associated with Alpha and beta emissions and these_________ produced outside the nucleus in the electron shell
gamma rays, x-rays
Columns are
groups
He
has 2 protons
Alpha particle
has a positive charge and mass
Gamma rays
has no mass or charge and comes from the nucleus
sodium and chloride are attracted to one another but result in an_________ because they have opposite electrostatic charge
ionic bond
occurs when two oppositely charged ions are attracted to each other
ionic bonding
When an orbital electron is removed from an atom.
ionized
Atomic Mass Unit
is more accurate
atoms that have the same number of neutrons but different protons are
isotones
atoms that have the same number of protons but different number of neutrons are
isotopes
The smallest particle of an compound is a
molecule
the smallest particle of a compound is a________ and the smallest particle of an element is an ______
molecule, atom
What electrical charge does an atom with an extra electron have
negative
what is the electric charge of a beta particles due to radioactive decay?
negative
Nucleons
neutrons + protons
group VII elements that are highly resistant to reactions with other elements
noble gases
ionizing radiation is either_________ or_______ radiation
particulate, electromagnetic
X-rays and gamma-rays are often called this form of electromagnetic energy
photons
Physicist calls the shell number "n" the __________
principal quantum number
The nucleus of every atom has at least one
proton
nucleons
protons + nucleons
the atomic number of elements is the number of
protons in the nucleus
these two particles are composed of quarks that are held together by gluons
protons, neutrons,( which are called nucleons)
this is the process where the nucleus spontaneously emits particles and energy and transfer itself into another atom
radioactive decay
the time required for the quantity of radioactivity to be reduced to one half its original value
radioactive half-life
radioisotopes
radioactive isotope
some atoms, which contain too many or too few neutrons in the nucleus can disintegrate. This is called
radioactivity
A radioactive atom.
radionuclide
rows in the Periodic table
relate to the number of electron shells present
Columns in the Periodic table
relate to the number of electrons in the outermost shells
Electron shells
represent different electron binding energies or energy levels
Alpha emission
results in arim transforms to another element ( loses two protons) and becomes negatively charged
half-life
time required for a quantity of radioactivity to be reduced by half
atoms cannot be ionized by the addition or subtraction of protons because they are bound very strongly together and that would change the type of atom. True or false
true
positive beta particles are positrons. true or false
true
the number of electrons in the outermost shell of an atom is equal to its group in the periodic table true or false
true
