Nuclear Chemistry

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protons and neutrons
atomic nuclei are made of _____________
protons and neutrons are collectively called _______
in nuclear chemistry, an atom is referred to as a(n) _________
protons and neutrons
the nuclide is identified as the number of ________________ in its nucleus
mass defect
the difference of the masses of the protons, neutrons, and electrons in an atom
conversion of mass energy upon formation of the nucleus
the mass defect is caused by the ____________________________________
the mass defect can be converted to energy using _______
nuclear binding energy
energy released when a nucleus is formed from nucleons or energy required to break apart the nucleus
binding energy
a measure of the stability of a nucleus
stronger nucleus is held together
the more energy lost=
dalton thought that atoms were ________
the process by which materials emit particles and energy __________
emissions of radioactivity
elements that give off radiation are said to be ____________
emitting radiation
scientists show that radioactive elements changed into other elements after _______ _______
radioactive decay
some nuclei are unstable and gain stability by emitting radiation through a process called __________________
chemical reactions
during __________, atoms tend to attain stability by transferring or sharing electrons; the nuclei remain unchanged
nuclear reactions
during _________, the nuclei of unstable isotopes gain stability by undergoing changes. theses changes are accompanied by the emission of large amounts of energy
nuclei of unstable isotopes:
sped up, slowed down, turned off
nuclear reactions cannot be _________,_______,_______
not chemically different from other isotopes of that element
electron structure
chemical reactivity depends on what?
nuclear decay
illustrates the interconnected nature of matter and energy
matter is related to energy according to ___________
speed of light
in e=mc², c=?
[alpha particles] have a(n) _______________ nucleus
[alpha particles] contains ____ protons and ___ neutrons
[alpha particles] ________ from nucleus
[alpha particles] charge of …
heavy nuclei
[alpha particles] restricted almost entirely to ____________
large mass and charge
[alpha particles] low penetrating power bc of _________________
alpha particles
sheet of paper or surface of skin will shield them; dangerous when ingested bc they travel a short distance to penetrate tissue and cause damage
alpha decay
a new element is formed when this happens along with the helium-4
nuclear equation
atomic and mass numbers are shown
high energy
[beta particles] _______ _______ electrons
[beta particles] charge of . . .
emitted from nucleus
[beta particles] ______ __ _____ when neutron is converted to proton and electron
[beta particles] atomic number increases by _____, and the mass number is increased by ____.
less charge and mass
[beta particles] less penetrating than alpha particle bc it has __________________
beta particle
can penetrate paper, but stopped by aluminum foil and thin pieces of wood
for every particle, there is a(n) __________
the antiparticle for electron=
electron capture
an inner orbital electron is captured by the nucleus of its own atom; inner orbital electron combines with a proton to form a neutron
gamma rays
high energy electromagnetic waves emitted from the nucleus as it changes from an excited state to a ground energy state
no mass or electrical charge
[gamma rays] possesses _ _______________ ______ ________ _________
alpha and beta radiation
[gamma rays] usually accompany ??
radioactive decay
[gamma rays] account for most energy lost during ________________.
[gamma rays] can be __________
gamma rays
penetrate paper, wood, and human body
gamma rays
stopped, although not completely- by several meters of concrete or several cm of lead
neutron-proton ratio
the stability of a nucleus depends on what?
band of stability
displays all stable nuclei
the band of stability ends at element _______
all nuclei that have an atomic number greater than 83 are _______________
an extremely small quantity of mass is converted into ______ released in radioactive decay
every radioisotope has a characteristic rate of decay measured by its ___________
the time required for half the atoms of a radioactive isotope to decay
decay series
series of radioactive nuclides produced by successive radioactive decay until a stable nuclide is produced
parent nuclide
the heaviest nuclide of each decay series
daughter nuclides
nuclides produced by the decay of the parent nuclide
the conversion of an atom of one element to an atom of another element
radioactive decay particles bombard the nucleus
transmutation can occur when…
many transmutations occur in __________
the earliest artificial transmutation was performed by ________
transuranium elements
the elements in the periodic table with atomic numbers above 92, the atomic number of uranium, are called ____________
[transuranium elements] all undergo ______
[transuranium elements] none occur in _______
[transuranium elements] all are ______
reactors and accelerators
[transuranium elements] have been synthesized in nuclear _________ and ________
artificial radioactive nuclides
are radioactive nuclides not found naturally on earth
artificial transmutations
bombardment of stable nuclei with charged and uncharged particles
nuclear fission
a very heavy nucleus splits into more stable nuclei of intermediate mass
fission produces enormous amounts of ________
uranium-235 and plutonium-239
the only 2 fissionable isotopes
chain reaction
a reaction in which the material that starts the reaction is also one of the products and can start another reaction
critical mass
the minimum amount of nuclide that provides the number of neutrons needed to sustain a chain reaction
atomic bombs
uncontrolled chain reactions provide the explosive energy of ________
nuclear reactors
use controlled-fission chain reactions to produce energy or radioactive nuclides
nuclear fusion
light-mass nuclei combine to form a heavier, more stable nucleus
more energy per gram
fussion releases _______ ______ ____ ______ of fuel than fission
fission reaction
used to provide the heat and pressure necessary to trigger the fusion of the nuclei
ionizing radiation
radiation emitted by radioisotopes is called______
ionizing radiation
radiation with enough energy to knock electrons off some atoms of the bombarded substance to produce ______
charged atoms
geiger counters, scintillation counters, film badges
devices used to detect radiation:
neutron activation analysis
procedure used to detect trace amounts of elements in samples; used by museums to detect art forgeries; used by crime labs to analyze gun-powder residues
radioisotopes used in agriculture to test the effects of herbicides, pesticides, and fertilizers; also monitored in animals that consumes the plants
_______ are used to diagnose medical problems
thyroid probs
iodine-131 is used to detect…
brain tumors and liver disorders
technetium-99 is used to detect…
skin cancer
phosphorus-32 us used to detect…
radiation therapy
used to kill cancerous cells (gamma rays)
narrow beam of gamma rays is directed at cancerous tissue
salts of radioisotopes are sealed and implanted in _______
Categories: Nuclear Chemistry