Chapter 8: Atoms and Periodic Properties
What statement correctly describes the procedure used to predict the ion formed by a representative element?
A metal loses enough electrons to attain the same number as its nearest noble gas.
What correctly describes the Pauli exclusion principle?
An orbital can hold a maximum of two electrons as long as they have opposite spins.
What is atomic weight?
Atomic weight is the weighted average, relative to carbon-12, of all naturally occurring isotopes for a given element.
The four lines that make up the visible region of the line spectra of hydrogen became known as the _____ series.
Balmer
What equation correctly reflects the relationship between energy and frequency?
E = hf
allowed orbits
Electrons can only exist in certain orbits.
radiationless orbits
Electrons do not emit light in their allowed orbits.
quantum leaps
Electrons move between orbits by absorbing or emitting exactly the energy different between the two orbits.
quantum mechanical model
Electrons occupy a three-dimensional space near the nucleus.
bohr model
Electrons occupy simple circular orbits that surround the nucleus.
What does it mean for energy to be quantized?
Energy is absorbed or emitted in discrete units.
What are isotopes?
Isotopes have different numbers of neutrons.
What is a consequence of the Heisenberg uncertainty principle?
It is not possible to assign an electron to a fixed orbit.
What correctly describes the limitations of the Bohr model of the atom?
The Bohr model cannot account for the behavior of multi electron species.
What is an electron volt?
The energy of an electron moving through a potential of 1 V
What is a statement that correctly describes the magnetic quantum number?
This value describes the orientation of orbitals in space around the nucleus.
What statements correctly describe the observations that led to the development of the nuclear model of the atom?
Thomson measured the charge-to-mass ratio for an electron; Rutherford determined that the mass of an atom is concentrated in the central region
Describe Thomson's model of the atom.
Thomson postulated that electrons are embedded in a massless blob of positive charge.
True or false: Line spectra of atoms in the gas phase do not show a continuous speed of frequencies.
True
An electron moves to a higher-energy orbit by ______ energy form high temperatures or electrical discharges, and moves to a lower-energy orbit by ______ energy in the form of light. The energy absorbed or emitted must exactly equal the energy_____ between the two orbits.
absorbing; emitting; difference
Group 1A
alkali metals
When comparing groups of representative elements, the ______ metals are the most reactive metals whereas the ______ are the most reactive nonmetals.
alkali; halogens
Group 2A
alkaline earth metals
What statements correctly describe electronic transitions in an atom?
an electron absorbs energy to move to a higher-energy orbit; the energy absorbed or emitted in an electronic transition is exactly equal to the energy difference between the two orbits
What two pieces of information must be known to calculate the atomic weight of a particular element?
atomic mass of each isotope; relative abundance of each isotope
What statements correctly describe Dalton's atomic theory?
atoms of the same element are identical; compounds result form the specific combination of a specific ratio of atoms of different elements; all matter consists of atoms
Dalton's atomic theory stated that matter consists of tiny indivisible particles called _____, which combine in definite whole-number ratios to form ______.
atoms; compounds
Dalton's atomic theory stated that matter consists of tiny indivisible particles called _______, which combine in definite whole-number ratios to form ______.
atoms; compounds
All atomic masses are determined relative to a(n) ______-12 standard; this isotope is defined to be exactly 12 u.
carbon
What are cathode rays?
cathode rays are identical no matter what their source; the discovery of cathode rays showed that an atom can be broken down into smaller particles; a cathode ray consists of negatively charged particles
The electron ______ of an element shows the distribution of electrons within the orbitals of the atom.
configuration
spin quantum number
direction of spin
What statements about line spectra of atoms in the gas phase is true?
each line in a line spectrum represents a specific energy; each atom has a characteristic line spectrum; atoms in the gas phase only emit radiation at certain frequencies
What is true about the rules of writing the electron configuration of an atom?
each orbital contains a maximum of two elements; the sum of the electrons in all orbitals is equal to the atomic number
What statements correctly describe the electron dot notation?
electron dot notation represents the outer electrons in a given element; the electron dot notation will be the same for all members of the same family
Thomson's experiments with cathode rays determined that atoms contained even smaller particles called _______, which have a _____ charge.
electrons; negative
The angular momentum quantum number describes _______. Each of these is identified with a ______.
energy sub levels; letter
angular momentum quantum number
energy sublevel
For an electrically neutral atom the number of protons is _____ the number of electrons.
equal to
The Pauli _____ principle states that no two electrons in the same atom can have the same four quantum numbers. This means that the maximum number of electrons accommodated by any orbital is _______.
exclusion; two
The vertical columns in the periodic table are called ______ and the horizontal rows are called ______.
families; periods
Representative elements that are in the same ______ of the periodic table will have the same ______ electron configuration and will have very similar chemical properties.
family; outer
Representative elements that are in the same ______ of the periodic table will have the same _______ electron configuration and will have very similar chemical properties.
family; outer
nonmetals
gain electrons to form negative ions
An electron in the _____ state will jump to a(n) ______ state when it absorbs a quantum that is equal to the difference in energy between the two states.
ground; excited
Group 7A
halogens
The charged particle that forms when an atom loses or gains electrons is called a(n)_____.
ion
What statements correctly describe wave-particle duality?
large objects have wavelengths that are too small to be detected or measured; all matter exhibits wavelike motion
metals
lose electrons to form positive ions
principal quantum number
main energy level of the electron
The _____ number of an atom is the sum of its protons and _____.
mass; neutrons
Transition elements, such as Fe, are ______ and tend to _____ electrons when forming ions. Transition elements are different from representative elements in that they tend to form ions with _____ charges.
metals; lose; variable
Rutherford's gold fold experiment was very important in developing the nuclear model of the atom. Which of the following statements correctly describe the observations made and the implications of each for atomic structure?
most alpha particles passed straight through the foil, implying that the atom consists largely of empty space; a few alpha particles showed major deflections, and some were reflected indicating the presence of a dense, positive core
In Rutherford's gold-foil experiment, he observed that most of the alpha particles passed straight through the foil, indicating that the atom is _____. Some alpha particles were deflected at large angles and others were reflected back toward the source, which caused him to conclude that the atom contains a dense, _____ charged nucleus surrounded by electrons.
mostly empty space; positively
In Rutherford's gold-foil experiment, he observed that most of the alpha particles passed straight through the foil, indicating that the atom is ________. Some alpha particles were deflected at large angles and others were reflected back toward the source, which caused him to conclude that the atoms contains a dense, charged nucleus surrounded by electrons.
mostly empty space; positively
When an electron is in the orbit closest to the nucleus, its value for potential energy will be _____. When an electron is completely removed from the nucleus, its potential energy is ______.
negative; zero
Group 8A
noble gases
An atom is composed of a very dense central ______ containing _______, which are positively charged, and neutrons, which have _______ electric charge.
nucleus; protons; no
What is a correct description of an orbital?
orbitals have characteristic shapes and sizes; an orbital defines the probability of finding an electron in a given region of an atom
What are the problems with the solar system model of the atom?
orbiting electrons wold accelerate; the solar system model of the atom describes a situation where the atom would collapse; orbiting electrons would emit light
magnetic quantum number
orientation in space
What correctly describes Rutherford's experiment to discover the nature of the atom?
particles were detected by a screen that produced small flashes of light when struck; measurements of the angles between the scree, metal foil, and the source determined the scatter pattern of the particles
Albert Einstein stated that light follows the quantum concept proposed by Planck, and consists of discrete units of energy called ____.
photons
An orbital defines the _____ of finding an electron in space.
probability
The atomic number of each element is unique and represents the number of ______ in the nucleus. Since an atom is neutral, this number is also equal to the number of _____ present.
protons; electrons
Energy is not continuous, but is quantized or divided into "packets," each of which contains a definite amount of energy. Energy "packets" are called ______ and the energy of each "packet" is directly proportional to its _____.
quanta; frequency
All elements in the A groups of the periodic table are called the ______ elements while the elements in the B groups are called the _______ elements.
representative; transition
What are the letters associated with energy sub levels in an atom?
s; p; d; f
What statements about the evolution of the atomic concept are true?
some Greek philosophers theorized that matter is continuous; Democritus stated that matter is composed of small indivisible particles called atoms
An electron not only moves around the nucleus but also _______ on its own axis. There are two possible orientations for this behavior and these are described by the _____ quantum number.
spins; spin
Electron dot notation consists of the ______ of the element and one dot for each _____ electron in an atom of the element.
symbol; outer
What statements are correct about the angular momentum quantum number?
the angular momentum quantum number defines energy sub levels with specific shapes; the angular momentum quantum number describes energy sub levels that are associated with each principle quantum number
What statements correctly describe the atomic number of an element?
the atomic number is equal to the number of protons in the nucleus; each element has its own unique atomic number
Millikan's oil-drop experiment
the determination of the charge on a single electron
Thomson's experiment with cathode rays
the discovery of the electron
Rutherford's metal-foil experiment
the discovery of the nucleus of the atom
What pieces of information are important when writing the electron configuration of an element?
the energy ordering of the orbitals; the number of orbital orientations; the number of electrons in the atom
What statements correctly describe subatomic particles?
the mass of an electron is negligible compared to the mass of a proton; the electrons are located outside the nucleus of an atom
What statements correctly describe the principle quantum number n?
the n can have any possible whole-number value; the n describes the distance of the electron form the nucleus
What statements correctly describe the current model of the atom?
the nucleus is a very small fraction of the total volume of the atom; the number of protons equals the number of electrons in a neutral atom; the mass of the atom is mostly the mass of the neutrons and protons
Balmer developed an equation based on the _____ line spectrum of the element _____. His equation allowed him to directly calculate the ______ of each line in the line spectrum.
visible; hydrogen; wavelength
All matter behaves as though it moves as a _______. The motion of any particle can be described by the de Broglie equation, which relates wavelength of a particle to its ____ and speed.
wave; mass
Louis de Broglie demonstrated that matter is similar to light in that it has properties characteristic of both _____ and particles. This theory helped to explain the anomalous behavior of _______ in an atom.
waves; electrons
When is the potential energy of an electron considered to be zero?
when the electron is removed from the atom