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