Ch 2: Atom Structure and Measurements Flashcards
quantifies radioactivity
Curie
List some properties of xray and gamma photons
ionize (high energy)
cannot be focused, refracted, or reflected
Can be restricted (collimate), filtered, absorbed and remitted
cannot see, hear, feel, or smell
causes certain materials to fluoresce
travels at the speed of light
radiation monitors are usually calibrated to what unit of measure
Roentgen (R) or milliroentgens (mR)
how to convert R to mR
divide by 1000 (move decimal three places to the left)
1 mR = 1/1000 R
What is the SI unit for Roentgen
C/kg
Coulombs per kg
What is RAD/Gy used to measure?
radiation absorbed dose
describes patient dose
amount absorbed into the body
How do you convert Gy to RAD
multiply by 100 (move decimal two places to the right)
1 Gy = 100 RAD
What does Rem (Sievert) measure?
quantity of radiation received from all sources
used for occupational exposure
used to address the possibility of damage (dose to biological effect)
How to convert from rem to SV?
divide by 100 (move decimal two places to left)
1 rem = 0.01 Sv
100 rem = 1 Sv
Convert mSv to Sv
divide by 1000 (move decimal three places to left)
1 mSv = 1/1000 Sv
What unit of measure would you use for each scenario?
1) Leakage radiation from tube
2) Cumulative lifetime dose of rad tech
3) Patient wants to know amount of radiation received for a certain xray
1) Reontgen (R)
2) Rem (Sv)
3) Rad (Gy)
What is the SI unit for Curie?
Becquerel (Bq)
How do unstable atoms try to achieve stability?
decay and releasing excess energy in the form of electromagnetic gamma radiation and particles
Where and what is Curie (Ci) used for most?
measure radioactivity in nuclear power plants and radiation therapy
commonly used in nuclear medicine (commonly use MilliCurie/mCi)
Atoms are ____ dimensional
3
Can atoms be divided?
No, they are indivisible
What is the Bohr atom?
his theory the atom has 3 fundamental components: electrons, neutrons, protons
T/F An atom is very solid, with limited space for electrons to orbit.
False
Atoms are composed of mostly space, electron orbits are large compared to the nucleus
A majority of an atoms mass is the ____
nucleus
Electrons orbit the nucleus at almost the speed of ____ in fixed, precise orbits
light
T/F An electron’s mass is 1/2000 of the mass of a proton or nuetron.
true
A change in the electric charge of an atom usually is due to what?
gain or loss of an electron
ionization
The nucleus is held together by a strong force called what?
binding energy
Describe some jobs of binding energy.
holds together the protons and neutrons
overcomes the tendency for like charges to repel
holds the electrons in their orbits
What are the letter values of the electron shells?
Starts at K at the innermost shell and works down the alphabet
T/F An electron shell always fills to capacity.
false
What happens to excess electrons when a shell is filled?
Starts a new shell
Binding energy is the minimum required energy to ____ an atom
split
What is the binding energy of a tungsten atom’s K shell?
69.5
quantifies radiation intensity in air
Roentgen
quantifies occupational exposure or dose equivalent
REM/Sievert
considers the type of radiation and biological affect (whats the damage)
REM
measures Xray intensity in air
roengten
quantifies energy deposited into tissue by all types ionizing radiation
REM/Sievert
total quantity of radiation
RAD
affected by intensity of radiation, SID, time
RAD/gray
classification elemental relationships based on # of protons, neutrons, electrons
Isos
atoms of elements have the same # of protons (atomic number) but different # of neutrons
Isotope
atoms of elements have same #of neutrons but different # of protons
Isotone
atoms of elements have same # of protons and neutrons (atomic #) but different # of electrons
Isobar
same atomic # and atomic mass # but vary in energy in nucleus
Isomer
Which Isos is used most in rad?
Isotopes
In the periodic table, periods are…
rows
Each period says what about those groups of elements?
same number of electron shells
atoms become more complex as period increases
period # = # of electron shells
In the periodic table, groups are arranged in…
columns
The group column says what about those atoms?
same number of electrons in their outer shell
Group # = # of electrons in outer shell
Atomic number is the same as the number of what?
protons
and electrons (stable atom)
atomic mass number is equal to what?
of protons and neutrons
A stable atom would have equal number of what?
Protons = electrons
Define an element
simplest for of a substance that composes matter
one type of atom in an element
Define a molecule
two or more atoms bonded together
Define a chemical compound
combo of elements (atoms) bonded together
Formula to determine max # of electrons a shell would hold is…
2n^2
Does an electron shell always fill to capacity?
Not in the case of the outer shell
Inner shells fill up
What happens if there are electrons left over if a shell is filled?
A new shell is formed (the outer shell) and the binding energy of that shell is distributed to the electrons to hold them in place (higher energy holding the electrons than if the shell were full)
What are the three fundamental components of an atom?
electrons
neutrons
protons
What is the electrical charge of each component of an atom?
electron - negative
neutron - no charge
proton - positive
Where are the components of an atom located in the atom?
electron - orbit outside the nucleus
neutron - within the nucleus
proton - within the nucleus
Describe an electrically neutral atom
same number of protons and electrons
How does an atom become negative or positively charged
negative charge - more electrons than protons
Positive charge - more protons than electrons
Electron shells are lettered beginning with K as the inner most shell.
Which electron shells have the most energy, the inner shell or the outer shell? Why??
inner shell
fewer electrons in those rings, so each one gets more energy distributed to it
The K shell will always hold a maximum of _______ electrons.
2
Two or more atoms bonded together are called…
molecules
Number of protons and neutrons that are in the nucleus of an atom is the ________ (number)
atomic mass number
Simplest form of a substance. Made of one type of atom. Unchanging number of protons.
element
The outermost shell will always hold a maximum of ______ electrons
8
What is the formula used to determine how many electrons will fit in each shell?
2n^2
Combinations of elements
compound
The number of protons in the nucleus
atomic number
Element whose atoms have same number of protons and neutrons but different amounts of ((energy)) within nuclei
isom(e)r
Element whose atoms have the same amount of ((protons)) but a different amount of neutrons.
isoto(p)es
Element whose atoms have different number of protons but the same ((atomic)) number
isob(a)rs
Element whose atoms have the same number of ((neutrons)) but a different number of protons
isoto(n)es
The columns on the periodic table are referred to as…
group
What is the same about the atoms in each column in the periodic table?
same number of electrons in the outer shell (valence electrons)
The column number says what about that atom?
How many valence electrons it has
The rows on the periodic table are referred to as…
periods
The period number says what about that atom?
the number of electron shells it has
What is the same about the atoms in each row of the periodic table?
same number of electron shells
Describe the two types of bonding that takes place to form molecules…
ionic - attraction of opposite charges, one will lose an electron while the other gains one
covalent - two or more atoms sharing electrons
Simplest form of a substance. Made of one type of atom. Unchanging number of protons
element
number of neutrons and protons that are in the nucleus of an atom
mass number
Two or more atoms bonded together
molecule
combinations of elements
compounds
the number of protons in the nucleus
atomic number
The mass number of an element is almost always ____ (larger/smaller) than the atomic number.
larger
On the periodic table, what components are typically shown on an element square and where are they located?
Chemical Symbol - two letters in the middle
Atomic mass number - on top or the larger number
Atomic number - on bottom or the smaller number
T/F All compounds are considered molecules, but not all molecules are compounds
True
Molecule - two or more atoms
Compound - two or more of combo of different atoms
