Flashcards in Ch. III and XI Deck (84):
The use of electricity to cause a chemical reaction is called
During electrolysis of molten sodium chloride, chloride anions move to the
Anode, which is positively charged
Cathode rays are
Deflected by electric fields
J.J. Thompson measured the electron's
In his oil-drop experiment, Millikan determined the charge of an electron by
Noting that the drops had either a certain minimum charge or multiples or that charge
When Roentgen saw an X-ray image of his hand, the bones were darker than the glowing paper because the X-rays were
Absorbed more by bone than by flesh
Radioactivity arises from elements that
Are unstable and emit radiation
The mass of an alpha particle is about
Four times that of a hydrogen atom
Compared to the charge on an electron (designated 1^-), the charge on an alpha particle is
A beta particle is an
The mass of a gamma ray is
The most persuasive evidence from Rutherford's gold-foil experiment was that
Most of the alpha particles went right through the foil, but a tiny fraction were deflected right back toward the source
Rutherford's gold-foil experiment showed that
The nucleus was tiny and positively charged
From his gold-foil experiment, Rutherford concluded that atoms mainly consist of
The positively charged part of the atom is its
The three basic components of an atom are
Protons, neutrons, and electrons
The identity of an element is determined by its
Number of atoms
How many electrons are required to equal the mass of one proton?
Which particles have approximately the same mass?
Protons and neutrons
A change in the number of protons in an atom produces an
Atom of a different element
The number of protons plus neutrons in an atom is its
How many protons (p) and how many neutrons (n) are there in a 15/7N nucleus?
7 protons, 8 neutrons
A neutron atom has 19 electrons and 20 neutrons. Its atomic number is
An atom has 16 neutrons. It is
Not possible to identify the element from the number of neutrons
The symbol for the isotope potassium -40 is
When electrified in a gas-discharge use, different elements emit light that forms narrow lines that are
Characteristic of each particular element
When an electron in an atom goes from a higher energy level to a lower one, the electron
An atom in an excited state is one with an electron that has
Moved to a higher energy level
The maximum number of electrons in the first shell of an atom is
The maximum number of electrons in the third shell of an atom is
The main-shell electron configuration of aluminum is
2, 8, 3
The main-shell electron configuration of sulfur is
2, 8, 6
The shape of a 1s orbital is
The maximum number of electrons in an atomic orbital
Is always 2
Which of the following subshells has the highest energy?
What is the lowest-numbered main shell to have "d" orbitals?
Which of the following atoms has a half-filled subshell in the ground state?
Which subshell has a total of three orbitals?
In what main shell is a 3d subshell located?
The electron capacity of the 4p subshell is
Which pair of elements has the most similar chemical properties?
Cl and Br
Elements within a period of the periodic table have the same number of
Occupied main shells
The valence-shell electron configuration of the halogens is
The alkali members are of group
What is the total number of valence electrons in an atom of bromine?
Which of the following sets of elements exhibits the most similar chemical properties?
Li, Na, and K
In the ground state, atoms of a fourth period element must have
Electrons in the fourth shell
What percentage of background radiation comes from natural sources?
The largest source of natural background radiation is
At present levels of exposure, which of the following forms of radiation is most likely to give you cancer?
What are the mass and the charge, respectively, of positron particles?
What particle is needed to complete the following nuclear equation?
9/4 Be + ___ ----> 12/6 C + 1/0 n
Emission of which of the following will result in an increase of 1 in atomic number?
Emission of which of the following will result in no change in atomic number or nucleon number?
For which type of radioactive decay is an electron found on the left side of the equation?
Which of the following is the largest particle?
A patient is given a 48-mg dose of technetium-99 m (half-life 6.0 h) to treat a brain cancer. How much of it will remain in his body after 36 h?
What is the half-life of arsenic-74 if a 50.0 g sample decays to 6.25 g in 53.7 d?
Of a 64.0-g sample of strontium-90 (half-life 28.5 y) produced by a nuclear explosion, what mass in grams would remain unchanged after 285 y?
Lead-210 (half-life 22.26 y) can be used to date skeletal remains. About how old is a bone that has an activity of 2.0 Bq if new bone has an activity of 16 Bq?
About how old is a piece of wood from an aboriginal burial site that has a carbon-14 (half-life 5370 y) activity of 3.9 counts/min per gram of carbon? Assume that the carbon-14 activity of the wood was 15.6 counts/min per gram of carbon at the time of the burial.
What isotope of formed in the following artificial transmutation?
14/7 N + 1/0 n ---> 1/1 H+ ___
14 C or Carbon-14
What isotope is formed in the following artificial transmutation?
9/4 Be + 1/1 H ---> 4/2 He + ___
6 Li or Lithium-6
What isotope is formed in the following artificial transmutation?
27/13 Al + 4/2 He ---> 1/0 n + ___
30 P or Phosphorus-30
Iodine-131 is sometimes used for detecting leaks in underground pipes because
It has a short half-life
What is used to irradiate foodstuffs to extend shelf life?
Which of the following isotopes is used in radiation therapy?
Which of the following isotopes is used in determining bone density?
Which of the following isotopes is used for detecting heart problems during a treadmill stress test?
Which of the following isotopes is used in thyroid diagnosis and therapy?
What form of radiation is detected in PET scans?
Which of the following pairs represent the least and most penetrating types of radiation?
Which form of radiation requires a thin sheet of aluminum to be stopped?
A Geiger counter registered 50 Bq or activity from an unknown type of radiation. A piece of paper inserted between the source and the counter caused the reading to drop to about 2 Bq. The radiation was mostly
Helium has a particularly high binding energy per nucleon, which means that it
Is more stable than H and Li
The most stable nuclei are those of
Nuclei with nucleon numbers greater than that of iron are
Less stable than that of iron
The isotope used in uranium fission reactions is
What fraction of natural uranium is the fissionable isotope?
The uranium isotope from which fissile plutonium-239 is made is
Strontium-90 substitutes for calcium in bones because Sr and Ca
Are in the same group of the periodic table
Many people in the Chernobyl and Tukushima areas were given large doses of potassium iodide to limit the uptake of iodine-131 and its concentration in the
Which of the following is not one of the isotopes produced by fission that presents the greatest hazard to people?