PSC ch 8
Which of the following is the correct electron configuration for vanadium?
1s22s22p63s23p64s23d3
What is the frequency of the energy emitted when the electron of a hydrogen atom moves from the n = 1 to the n = 2 energy level? (Round the answer to two decimal places.)
2.47
The energy of a photon of light with a frequency of 4.3 x 1014 Hz is
2.85
An unknown element has two primary isotopes, one with a relative abundance of 25.34 percent and a mass of 52.35 u, and another with a relative abundance of 74.66 percent and a mass of 54.87 u. What is the atomic weight of this element? Multiple choice question.
54.23 u
Which element has the electron configuration 1s22s22p63s23p1?
Al
Which of the following statements correctly describe wave-particle duality? (Select all that apply.)
All matter exhibits wavelike motion. Large objects have wavelengths that are too small to be detected or measured.
Which of the following statements correctly describe electronic transitions in an atom? (Select all that apply.)
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
Which of the following statements correctly describe the Bohr model? (Select all that apply.) Multiple select question.
An electron can only exist in fixed orbits around the nucleus. An electron in an allowed orbit does not emit radiant energy as long as it remains in the orbit.
Which of the following statements correctly describe an orbital? (Select all that apply.)
An orbital defines the probability of finding an electron in a given region of an atom. Orbitals have characteristic shapes and sizes.
Which of the following statements about line spectra of atoms (pictured) in the gas phase is true? (Select all that apply.)
Atoms in the gas phase only emit radiation at certain frequencies. Each atom has a characteristic line spectrum. Each line in a line spectrum represents a specific energy.
Which of the following statements correctly describe Dalton's atomic theory? (Select all that apply.)
Atoms of the same element are identical. All matter consists of atoms. Compounds result from the specific combination of a specific ratio of atoms of different elements.
The four lines that make up the visible region of the line spectra of hydrogen became known as the ________ series, named after the person who developed an equation to determine the wavelength of each line.
Balmer
An unknown element has two primary isotopes, one with a relative abundance of 99.63 percent and a mass of 14.00307 u, and another with a relative abundance of 0.37 percent and a mass of 15.0011 u. What is the atomic weight of this element?
Blank 1: 14.0068
Equal to 1/12 the mass of a carbon-12 atom, the _________ __________ _________ is used to describe the relative mass of an atom.
Blank 1: atomic Blank 2: mass Blank 3: unit
The electron ________ of an element shows the distribution of electrons within the orbitals of the atom.
Blank 1: configuration
The energy of an electron moving through a potential of 1 volt is called a(n)
Blank 1: electron Blank 2: volt
The Heisenberg uncertainty principle states that it is not possible to know the exact momentum and _________ of an electron simultaneously. In terms of atomic structure, this means that we cannot determine fixed orbits for electrons but can only determine the _________
Blank 1: position or location Blank 2: probability or possibility
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 ________
Blank 1: waves Blank 2: electrons
Which of the following statements correctly describe cathode rays? (Select all that apply.)
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.
Which of the following is the ion formed by an atom of Cs? Multiple choice question.
Cs+
Which of the following statements about the evolution of the atomic concept are true? (Select all that apply.)
Democritus stated that matter is composed of small indivisible particles called atoms. Some Greek philosophers theorized that matter is continuous.
Which of the following statements correctly describe the atomic number of an element? (Select all that apply.)
Each element has its own unique atomic number. The atomic number is equal to the number of protons in the nucleus.
Which of the following are true about the rules of writing the electron configuration of an atom? (Select all that apply.)
Each orbital contains a maximum of two electrons. The sum of the electrons in all orbitals is equal to the atomic number.
Which of the following statements can be attributed to the quantum mechanical model of the atom? (Select all that apply.)
Electrons occupy a three-dimensional space near the nucleus. The wave nature of the electron is emphasized.
Which of the following options correctly describe the arrangement of the periodic table? (Select all that apply.)
Elements in the same family have similar chemical properties. The horizontal rows of the periodic table are called periods.
What does it mean for energy to be quantized? Multiple choice question.
Energy is absorbed or emitted in discrete units.
Which statement correctly describes what occurs when the electron of the hydrogen atom moves from the n = 1 to the n = 3 energy level? Use the provided energy level diagram of hydrogen to answer this question.
Energy with a frequency of 2.92 x 1015 Hz is absorbed by the atom.
Which of the following statements correctly describes isotopes?
Isotopes have different numbers of neutrons.
Select all the statements that accurately characterize the quantum mechanics theory of the atom. Multiple select question.
It considers the wave nature of electrons. It states where electrons might be found, rather than where they definitely are.
What is a consequence of the Heisenberg uncertainty principle?
It is not possible to assign an electron to a fixed orbit.
Which of the following statements correctly describe wave-particle duality? (Select all that apply.) Multiple select question.
Large objects have wavelengths that are too small to be detected or measured. All matter exhibits wavelike motion.
Which of the following statements correctly describe the properties of a photon? (Select all that apply.) Multiple select question.
Matter cannot absorb or emit a fraction of a photon. Photons are discrete units of light energy.
Which of the following options correctly describe Rutherford's experiment to discover the nature of the atom? (Select all that apply.
Measurements of the angles between the screen, metal foil, and the source determined the scatter pattern of the particles. Particles were detected by a screen that produced small flashes of light when struck.
Which of the following options correctly describe the results of the experiments performed by Thomson and Millikan? (Select all that apply.)
Millikan measured the electrical charges of oil droplets. Millikan's experiments allowed him to calculate the charge and mass of the electron. Thomson studied the behavior of cathode rays.
Rutherford's gold foil 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? (Select all that apply.)
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.
Which of the following options correctly describe the problems with the solar system model of the atom? (Select all that apply.) Multiple select question.
Orbiting electrons would emit light. Orbiting electrons would accelerate. The solar system model of the atom describes a situation in which the atom would collapse.
Which of the following properties are described by the angular momentum, principal, spin, and magnetic quantum numbers? (Select all that apply.)
Orientation in space Energy Direction of spin
Which of the following statements correctly describe the properties of a photon? (Select all that apply.) Multiple select question.
Photons are discrete units of light energy. Matter cannot absorb or emit a fraction of a photon.
An orbital defines the ____of finding an electron in space.
Probability
What two pieces of information must be known to calculate the atomic weight of a particular element?
Relative abundance of each isotope Atomic mass of each isotope
What is the limitation of the Bohr model of the atom?
The Bohr model cannot account for the behavior of multielectron species.
What does the Bohr equation (shown) allow one to calculate? Multiple choice question.
The allowed energies of the electron in a hydrogen atom
Which of the following statements about the angular momentum quantum number is true? (Select all that apply.)
The angular momentum quantum number defines energy sublevels with specific shapes. The angular momentum quantum number describes energy sublevels that are associated with each principal quantum number.
Which of the following statements correctly describe subatomic particles? (Select all that appl
The electrons are located outside the nucleus of an atom. The mass of an electron is negligible compared to the mass of a proton.
A particular isotope of an element is represented by the symbol 79357935Br. Which of the following options correctly interpret this symbol? Multiple select question.
The element contains 44 neutrons in the nucleus. The element contains 35 protons in the nucleus.
Which of the following pieces of information are important when writing the electron configuration of an element? (Select all that apply.) Multiple select question.
The energy ordering of the orbitals The number of electrons in the atom The number of orbital orientations
What does the equation based on the Bohr model of the atom (shown) allow one to calculate?
The energy that is emitted or absorbed when the hydrogen electron moves between energy states
Which of the following statements correctly describe the mass number of an element? (Select all that apply.)
The mass number is given by the sum of the protons and neutrons in the nucleus. The mass number is often written as a left superscript next to the chemical symbol.
Which of the following statements correctly describe the principal quantum number n? Multiple select question.
The n can have any whole-number value. The n describes the distance of the electron from the nucleus.
Which of the following options correctly describe the chemical and physical properties of the representative elements in the periodic table? (Select all that apply.) Multiple select question.
The noble gases are generally chemically inert. Alkali metals react violently with water.
Which of the following correctly describe the current model of the atom? (Select all that apply.) Multiple select question.
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.
Which of the following statements correctly describe the spin quantum number? (Select all that apply.)
The spin quantum number is a property of the electron itself. The spin quantum number has two possible values.
Which of the following are true about the rules of writing the electron configuration of an atom? (Select all that apply.)
The sum of the electrons in all orbitals is equal to the atomic number. Each orbital contains a maximum of two electrons.
Which of the following options interpret the electron configuration 1s22s22p3 correctly? (Select all that apply.)
There are 2 electrons in the 1s sublevel. The 2 electrons in the 2s sublevel have opposite spin.
Which of the following accounts for the observation that Mg, Ca, Sr, and Ba have similar chemical properties? Multiple choice question.
They have the same outer electron configuration.
Which of the following statements correctly describe the magnetic quantum number? (Select all that apply.)
This value describes the orientation of orbitals in space around the nucleus.
Which of the following statements about Thomson's model of the atom is true?
Thomson postulated that electrons are embedded in a massless blob of positive charge.
An electron moves to a higher-energy orbit by ______ energy from 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
When comparing groups of representative elements, the _____ metals are the most reactive metals, whereas the _____ are the most reactive nonmetals.
alkali; halogens
Isotopes are atoms of the same element that have the same ______ number but a different ______ number. This is because isotopes have the same number of protons but a different number of ______. Multiple choice question.
atomic; mass; neutrons
Dalton's atomic theory stated that matter consists of tiny indivisible particles called _________ which combine in definite whole-number ratios to form __________
atoms Compounds
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 sublevels; letter
The quantum mechanics model describes the location of electrons as ______. Multiple choice question.
fuzzy statistical representations
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
Thomson discovered that cathode rays emanate from the ______ electrode. This among other experimental evidence caused him to postulate that they consist of particles of the same charge. However, the major breakthrough made by Thomson was that the charge-to-mass ratio of the particles that make up cathode rays are ______ for each source.
negative; the same
Albert Einstein stated that light follows the quantum concept proposed by Planck and consists of discrete units of energy called
photons
Since it was known that the atom was electrically neutral, Thomson proposed that the atom was a massless blob of _____ charge with _____ charged particles embedded in it like "raisins in plum pudding."
positive; negatively
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
The electron configuration of an element describes _____.
the distribution of electrons within the orbitals of the atom
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. Multiple choice question.
visible; hydrogen; wavelength
