Chemistry:Atoms First- Chapter 3 Part 1 (Knewton based questions)

Which core electrons are implied by the symbol [Ne]?

Neon has the electron configuration 1s22s22p6, so these are the core electrons that are implied when an element is listed as having a neon core.

The work of Niels Bohr relied on the assumption that:

Niels Bohr solved the atomic paradox by ignoring classical electromagnetism. He assumed that the electron orbiting the nucleus would only emit radiation when it emits a photon as it moves to a lower-energy orbit.

According to the Heisenberg uncertainty principle, quantum mechanics differs from classical mechanics in that:

Quantum mechanics differs from classical mechanics in that measurements of certain observables in the quantum domain introduce changes to the system, a fact that is governed mathematically by Heisenberg's uncertainty principle.

If we say 2p6, the 2 corresponds to:

The 2 is the n value for those orbitals, which tells us the energy level of the electrons in that subshell. The 6 tells us how many electrons are in that orbital.

The 5p orbitals fill immediately after the 4d orbitals and immediately before the 6s because:

The 5p orbitals fill immediately after the 4d orbitals and immediately before the 6s based on observed experimental results, and has been supported by theoretical calculations.

An increase in the wavelength of electromagnetic radiation is associated with which of the following? Increase in frequency, decrease in frequency, no change in frequency

a decrease in frequency. Wavelength and frequency are inversely proportional: As the wavelength increases, the frequency decreases. The inverse proportionality is illustrated in the figure below. This figure also shows the electromagnetic spectrum, the range of all types of electromagnetic radiation.

Before the work of Albert Einstein and other prominent scientists of the early 1900's, the predominant view among physicists was that light is:

a wave. The predominant view before Einstein's work with the photoelectric effect was that light is wave. Scientists now recognize that light can behave as both a particle and a wave.

The current view proposes that light is: (A)composed of waves, (B)composed or particles, (C)composed of both waves and particles, (D)interference

composed of both waves and particles (wave-particle duality). Newton believed light was composed of particles and Maxwell believed light was composed of waves, but we now believe light is both wavelike and particle-like.

If mass and velocity are unknown when using de Broglie's wavelength formula, what alternative value must we have to successfully determine the wavelength?

de Broglie's wavelength formula is λ=h/p or λ=h/mv. Therefore if we are unable to determine mass and velocity, we must know the momentum of the particle.

For objects with the same uncertainty in velocity, the minimum uncertainty in the position _________

decreases with increasing mass. Because the minimum value of the product ΔxΔp is a constant, and because p=mv, this implies that (Δx)(mΔv) also has a minimum value. The minimum uncertainty in position Δx and the mass m are inversely proportional by the equation above: if m increases, and Δv remains constant, the minimum value of Δx decreases. This is why we cannot observe the effects of the Heisenberg Uncertainty Principle on macroscopic objects.

Which of the following is a violation of the Pauli Exclusion Principle? (A) n = 1,2,3,4,...(B)0≤l≤n−1 (C)ml =−l (D)ms = +3/2

ms = +3/2. An orbital can hold 0,1, or 2 electrons only. If there are two electrons in the orbital, they must have opposite spins (−1/2 and +1/2). +3/2 is not a possible value for ms.

Which electron spin state has the lower energy in the absence of an external magnetic field? (A)ms=+1/2 (B)ms=−1/2 (C)ms=+1/2 and ms=−1/2 have the same energy.(D)There is not enough information to answer this question.

ms=+1/2 and ms=−1/2 have the same energy.

According to Hund's rule, the orbital diagram for nitrogen will be:

one up and one down arrow in 1s box, one up and one down arrow in 2s box, and one up arrow in each of the three 2p boxes

The quantum-mechanical model of the atom changed our view of which subatomic particle?

the electron

If we say 3d4, the 4 corresponds to:

the number of electrons in those orbitals

For the purposes of determining electron configuration of ions, when electrons are added to a neutral atom, they will inhabit orbitals according to: (A)the Pauli exclusion principle (B) the Aufbau principle (C)Hunds Rule (D) all of the above

All of the above

What is the electron configuration for Cl−?

1s22s22p63s23p6

What is the electron configuration for Zn2+?

1s22s22p63s23p63d10

What is the ground state configuration of calcium? (Ca)

1s22s22p63s23p64s2

What is the electron configuration of Br if it loses three electrons?

1s22s22p63s23p64s23d104p2

What are the core electrons of strontium?

1s22s22p63s23p64s23d104p6

What is the electron configuration for Ru3+

1s22s22p63s23p64s23d104p64d5

The orbitals that are next highest in energy after the 4s orbital are the:

3d orbitals

Which orbital holds the valence electrons of barium?

6s. Barium is in group 2, which is in the s block, and it is in period 6, so the 6s orbital will be the orbital that holds its valence electrons.

An electron jumps from the 3rd to the 4th energy level of an atom. What can we assume about this atom?

" Bohr discovered that an electron will transition from one energy level to another when a photon of a very specific energy is either absorbed or emitted by an electron.

none of the above"

none of the above. They could have the same principle quantum number if they are in different orbitals with the same shell, they could have the same angular momentum quantum number if they are in different orbitals of the same type of subshell, and they could have the same spin value, as every full orbital will have one electron spin up and one spin down.

When drawing orbital diagrams, each orbital is represented as a box. For example, an s subshell is represented by 1 box, and a p subshell is represented by 3 boxes. How many boxes are required to depict an f subshell?

Each box represents an orbital, and an f subshell contains 7 orbitals, regardless of the principle quantum number. Therefore there seven boxes are required to depict an f subshell.

In an orbital diagram, each small box represents which of the following? (A) a shell, (B) a subshell (C)an individual orbital (D) an individual orbital

Each box represents one orbital, each of which can hold two electrons.

________ is energy transmitted by waves that have an electric field component and a magnetic field component.

Electromagnetic radiation is energy transmitted by waves that have an electric field component and a magnetic field component.

What is electromagnetic radiation?

Electromagnetic radiation is the energy transmitted by waves with an electric and a magnetic field component.

________________ the certainty in one parameter necessarily means _________________ the uncertainty in the other.

Increasing, increasing.

The order in which orbitals are listed on an orbital diagram follows:

Orbitals are filled according to Hund's rule and they contain electrons possessing quantum numbers dictated by the Pauli exclusion principle, but the order in which they are listed follows the Aufbau principle.

Which element, when it gains two electrons, will have the electron configuration 1s22s22p63s23p64s23d104p6?

Se

Identify the element from the electron configuration: [Ar]4s23d2.

Ti

Which ion is isoelectronic with xenon?

Ba2+

The Aufbau principle states that:

Orbitals will be filled in order of increasing energy, which is generally in order of principal quantum number, with higher angular momentum subshells sometimes exceeding the energy of shells with higher n.

Which of the following increases with increasing energy? Principal quantum number, angular momentum quantum number, both, neither

The principal quantum number and the angular momentum quantum number increase with increasing energy.

Which of the following is a form of electromagnetic radiation? Sound wave, visible light, mechanical wave

Visible light. Visible light is a form of electromagnetic radiation. Visible light and other forms of electromagnetic radiation are important because they can be used to infer the energies of electrons within atoms and molecules.

The success of Bohr's model that demanded the scientific community's attention was its ability to:

calculate the Rydberg constant. The Rydberg constant was one of the most precisely measured constants of the time, so when Bohr's model calculated this constant to be in excellent agreement with the experimentally determined value, it was impossible to deny the validity of his model for the hydrogen atom.

The Schrödinger equation was developed directly from the:

de Broglie relation

When referring to electron configuration, the notation 4d8 indicates that there are

8 electrons in the d subshell

What are the core electrons in phosphorus?

1s22s22p6

What is the electron configuration for K+?

1s22s22p63s23p6

Which of the following formulas gives us the total number of possible orbitals with the same value of l? (A) 2l-1 (B) 2l+1 (C)2l/3 (D)2l

2l+1 gives us the total number of possible orbitals with the same value as l.

Which of the following has the highest energy level? (A)4s (B)3d (C)2p (D)3s

3d has the highest energy level of the choices because s<p<d<f.

Which type of orbital could NOT have an ml value of 2? (A) 3p (B) 3d (C) 4d (D)4f

3p. Any p orbital can only have an ml value of −1,0, or 1.

After de Broglie proposed the wave nature of matter, Davisson and Germer demonstrated the wavelike behavior of electrons by observing an interference pattern from electrons passing through what?

A nickel crystal

Nonmetals tend to gain electrons to obtain a noble gas electron configuration. (D) none of the above"

A nonmetal will tend to gain a number of electrons that will give it the electron configuration of the nearest noble gas, meaning a full valence shell, which is a stabilizing characteristic.

Which of the following quantum numbers describes an electron in an atom? Select all that apply. (a) l (b) n (C) ml (d) ms

All are correct

According to Bohr's model, when does an electron emit electromagnetic radiation?

An electron emits electromagnetic radiation when it is changing from one orbit to another, specifically from an orbit of higher energy to a lower one.

Bohr theorized that _________ were restricted to certain orbits of discrete energies.

Bohr theorized that electrons were restricted to certain orbits of discrete energies.

Bohr used an electron moving in a circular orbit about a nucleus to describe what?

Bohr used an electron moving in a circular orbit about a nucleus to describe the model of a hydrogen atom.

Which of the following is a rule indicated by the Aufbau principle?(A) Electrons fill subshells in order of principle quantum number first, and then by subshell (s before p before d...) (B) Electrons are placed in the lowest energy subshell that is not fully occupied. (C)One electron is placed in each subshell until the electron configuration accounts for all electrons. (D) all of the above

Electrons are placed in the lowest energy subshell that is not fully occupied.

According to the Bohr model, only when do electrons emit or absorb a photon?

Electrons only emit or absorb a photon if they move to a different orbit within the atom.

[The] _______states that the lowest-energy configuration for an atom with electrons within a set of degenerate orbitals is that having the maximum number of unpaired electrons.

Hund's rule states that the lowest-energy configuration for an atom with electrons within a set of degenerate orbitals is that having the maximum number of unpaired electrons.

What does the Heisenberg uncertainty principle state?

It is impossible to know both the position and the momentum of a particle with certainty.

Which element, when it loses one electron, will have the electron configuration 1s22s22p63s23p6?

K

What is the symbol for the following ion electronic structure: [Ne]3s23p6 with an atomic number of 16?

S2-. Atomic number 16 corresponds to S but there are 2 more electrons than S usually has so we know that S had to gain (−2).

Which of the following is true? (A)The closer an electron is to the nucleus, the higher its energy level. (B)The closer an electron is to the nucleus, the lower its energy level. (C)The closer an electron is to the nucleus, the more its energy level fluctuates. (D) There is no relationship between proximity to the nucleus and the energy level of an electron.

The closer an electron is to the nucleus, the lower its energy level. As an electron gets farther from the nucleus, its energy level is higher, and it is easier to remove from the nucleus.

The electromagnetic radiation theory shows that _______ is a part of the electromagnetic spectrum.

The electromagnetic radiation theory shows that visible light is part of the electromagnetic spectrum.

What is an assumption Bohr made about the hydrogen atom?

The electron is not continuously emitting electromagnetic radiation. Previously, it was suggested mathematically that the electron must be continuously emitting electromagnetic radiation. In Bohr's model, he countered this assumption.

Which of the following have the last electron added in an s or p orbital? (A)main group elements (B)transition elements (C)inner transition elements (D) all of the above

The main group elements have the last electron added in an s or p orbital.

What can be used to determine the distribution of the electron density with respect to the nucleus?

Wavefunctions are used to determine the distribution of the electron density with respect to the nucleus in an atom.

Wavelength (λ) is the ________________, frequency (ν) is the __________________, and they are related by the equation _________________.

Wavelength is the distance between two consecutive peaks or troughs in a wave. Frequency is the number of wave cycles that pass a specified point in space in a specified amount of time. And wavelength and frequency are related by the following equation, c=λν, where c is the speed of light.

What does the Aufbau principle prescribe?

We start with the lowest energy orbitals and build up to the higher energy orbitals until all electrons are assigned to an orbital.

What is the electron configuration of Na+?

[Ne] and 1s2 2s2 2p6

How did Schrodinger visualize electrons?

as three-dimensional wavefunctions. Louis de Broglie viewed electrons as circular standing waves and Bohr thought of them as particles moving in quantized circular orbits. Schrodinger initially thought of them as physical waves, but later viewed them as three-dimensional wavefunctions. The wavefunctions are represented in the equation, H^ψ=Eψ as the Greek letter ψ.

Elements that have similar electron configurations belong to the same:

group

Every ________ will have its own unique set of quantum numbers.

individual electron

According to the equation developed by de Broglie, what happens to the wavelength of a particle as mass increases?

it decreases

Which of the following labels are used for quantum numbers to describe the state of an electron inside an atom? Select all that apply. (A) l (B)m (C)m0 (D)ms

l, ms. The magnetic quantum number (mℓ), the spin quantum number (ms), the principal quantum number (n), and the angular momentum quantum number (ℓ) all describe electrons within atoms. (m) and (mo) are not labels used to describe the state of an electron in an atom.

Each row on the periodic table corresponds to which quantum number for s and p orbitals?

principal quantum number

The _____________________ defines the general value of the electronic energy, while the _____________________________ determines the shape of the orbital.

principal quantum number; angular momentum quantum number. The principal quantum number corresponds to the energy of an orbital (as in the Bohr model), while the angular momentum quantum number corresponds to the unique shape of the orbital (labeled s,p,d, or f).

If two orbitals reside within the same subshell, they MUST have the same:

principle quantum number

For elements in the d block, the first electron removed will be a(n):

s electron. Even though d electrons were the last to be added for an element in the d block, and the d orbitals are slightly higher in energy than the s orbital immediately preceding, these elements will lose their outermost s electrons first.

The complementary values most widely associated with the Heisenberg Uncertainty Principle are momentum (p) and location (x). Another set of complementary variables for which this principle applies is which of the following?

time and energy. Momentum and location are inextricably related to the time and energy of an electronic transition (which constitute another set of complementary values). This means that the Heisenberg Uncertainty Principle applies to these variables as well: reduced uncertainty in one means greater uncertainty in another.

What is the equation to solve for a wavelength?

λ=c/ν

The de Broglie wavelength is represented by the expression:

λ=h/mv