Question 1

A ground-state chromium atom has how many unpaired electrons?

Accepted Answer

A) 1 
B) 2 
C) 4 
D) 5 
E) 6 
A) 1 
B) 2 
C) 4 
D) 5 
E) 6

Question 2

Calculate the wavelength, in nanometers, of the light emitted by a hydrogen atom when its electron falls from the n = 7 to the n = 4 principal energy level. Recall that the energy levels of the H atom are given by En = -2.18 * 10-18 J(1/n2)

Accepted Answer

A) 4.45 * 10-20 nm 
B) 2.16 * 10-6 nm 
C) 9.18 * 10-20 nm 
D) 1.38 * 1014 nm 
E) 2.16 * 103 nm 
A) 4.45 * 10-20 nm 
B) 2.16 * 10-6 nm 
C) 9.18 * 10-20 nm 
D) 1.38 * 1014 nm 
E) 2.16 * 103 nm

Question 3

Calculate the frequency of the light emitted by a hydrogen atom during a transition of its electron from the n = 6 to the n = 3 principal energy level. Recall that for hydrogen En = -2.18 * 10-18 J(1/n2).

Accepted Answer

A) 1.64 * 1015 /s 
B) 9.13 * 1013 /s 
C) 3.65 * 1014 /s 
D) 1.82 * 10-19 /s 
E) 2.74 * 1014/s 
A) 1.64 * 1015 /s 
B) 9.13 * 1013 /s 
C) 3.65 * 1014 /s 
D) 1.82 * 10-19 /s 
E) 2.74 * 1014/s

Question 4

A ground-state atom of iron has ___ unpaired electrons and is _____.

Accepted Answer

A) 0, diamagnetic 
B) 6, diamagnetic 
C) 3, paramagnetic 
D) 5, paramagnetic 
E) 4, paramagnetic 
A) 0, diamagnetic 
B) 6, diamagnetic 
C) 3, paramagnetic 
D) 5, paramagnetic 
E) 4, paramagnetic

Question 5

A photon is roughly 1800 times more massive than an electron. If a proton and an electron have the same kinetic energy,

Accepted Answer

A) the wavelength of the photon will be about 1800 times longer than the wavelength of the electron. 
B) the wavelength of the photon will be about   times longer than the wavelength of the electron. 
C) the wavelength of the photon will be roughly equal to the wavelength of the electron. 
D) the wavelength of the electron will be about   times longer than the wavelength of the photon. 
E) the wavelength of the electron will be about 1800 times longer than the wavelength of the photon. 
A) the wavelength of the photon will be about 1800 times longer than the wavelength of the electron. 
B) the wavelength of the photon will be about   times longer than the wavelength of the electron. 
C) the wavelength of the photon will be roughly equal to the wavelength of the electron. 
D) the wavelength of the electron will be about   times longer than the wavelength of the photon. 
E) the wavelength of the electron will be about 1800 times longer than the wavelength of the photon.

Question 6

A photovoltaic cell converts light into electrical energy. Suppose a certain photovoltaic cell is only 63.5% efficient, in other words, that 63.5% of the light energy is ultimately recovered. If the energy output of this cell is used to heat water, how many 520 nm photons must be absorbed by the photovoltaic cell in order to heat 10.0 g of water from 20.0°C to 30.0°?

Accepted Answer

1.72 * 10<

Question 7

Which one of the following sets of quantum numbers is not possible?

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 8

Which ground-state atom has an electron configuration described by the following orbital diagram?

Accepted Answer

A) phosphorus 
B) germanium 
C) selenium 
D) tellurium 
E) none of these 
A) phosphorus 
B) germanium 
C) selenium 
D) tellurium 
E) none of these

Question 9

The electron configuration of a ground-state Co atom is

Accepted Answer

A) [Ar]4s23d7. 
B) 1s22s22p63s23d9. 
C) [Ne]3s23d7. 
D) [Ar]4s13d5. 
E) [Ar]4s24d7. 
A) [Ar]4s23d7. 
B) 1s22s22p63s23d9. 
C) [Ne]3s23d7. 
D) [Ar]4s13d5. 
E) [Ar]4s24d7.

Question 10

The electron in a hydrogen atom falls from an excited energy level to the ground state in two steps, causing the emission of photons with wavelengths of 1870 and 102.5 nm. What is the quantum number of the initial excited energy level from which the electron falls?

Accepted Answer

A) 2 
B) 3 
C) 4 
D) 6 
E) 8 
A) 2 
B) 3 
C) 4 
D) 6 
E) 8

Question 11

Which of the following is the electron configuration of an excited state of an iron atom?

Accepted Answer

A) [Ar]4s23d7 
B) [Ar]4s23d6 
C) [Ar]4s23d8 
D) [Ar]4s13d7 
E) [Ar]4s13d5 
A) [Ar]4s23d7 
B) [Ar]4s23d6 
C) [Ar]4s23d8 
D) [Ar]4s13d7 
E) [Ar]4s13d5

Question 12

Calculate the wavelength associated with a 20Ne+ ion moving at a velocity of 2.0 * 105 m/s. The atomic mass of Ne-20 is 19.992 amu.

Accepted Answer

A) 1.0 * 10-13 m 
B) 1.0 * 10-16 m 
C) 1.0 * 10-18 m 
D) 9.7 * 1012 m 
E) 2.0 * 10-13 cm 
A) 1.0 * 10-13 m 
B) 1.0 * 10-16 m 
C) 1.0 * 10-18 m 
D) 9.7 * 1012 m 
E) 2.0 * 10-13 cm

Question 13

Calculate the wavelength of a neutron that has a velocity of 250 cm/s. (The mass of a neutron = 1.675 * 10-24 g; h = 6.626 * 10-34 J.s)

Accepted Answer

A) 16 pm 
B) 0.016 nm 
C) 0.16 nm 
D) 160 nm 
E) 1.6 * 10-4 m 
A) 16 pm 
B) 0.016 nm 
C) 0.16 nm 
D) 160 nm 
E) 1.6 * 10-4 m

Question 14

What is the binding energy (in J/mol or kJ/mol)of an electron in a metal whose threshold frequency for photoelectrons is 2.50 * 1014 /s?

Accepted Answer

A) 99.7 kJ/mol 
B) 1.66 * 10-19 J/mol 
C) 2.75 * 10-43 J/mol 
D) 7.22 * 1017 kJ/mol 
E) 1.20 * 10-6 J/mol 
A) 99.7 kJ/mol 
B) 1.66 * 10-19 J/mol 
C) 2.75 * 10-43 J/mol 
D) 7.22 * 1017 kJ/mol 
E) 1.20 * 10-6 J/mol

Question 15

According to de Broglie's equation, the wavelength associated with the motion of a particle increases as the particle mass decreases.

Accepted Answer

A) True 
 B)False

Question 16

The ground-state electron configuration of Cr, Mo, and Ag are exceptions to the Aufbau principle. Which of the following is the electron configuration for Mo?

Accepted Answer

A) [Kr]5s14d5 
B) [Kr]5s24d4 
C) [Xe]6s25d4 
D) [Ar]4s24d4 
E) [Kr]5s24d6 
A) [Kr]5s14d5 
B) [Kr]5s24d4 
C) [Xe]6s25d4 
D) [Ar]4s24d4 
E) [Kr]5s24d6

Question 17

Calculate the frequency of the light emitted by a hydrogen atom during a transition of its electron from the n = 4 to the n = 1 principal energy level. Recall that for hydrogen En = -2.18 * 10 -18 J(1/n2)

Accepted Answer

A) 3.08 * 1015 /s 
B) 1.03 * 108 /s 
C) 2.06 * 1014 /s 
D) 1.35 * 10-51 /s 
E) 8.22 * 1014 /s 
A) 3.08 * 1015 /s 
B) 1.03 * 108 /s 
C) 2.06 * 1014 /s 
D) 1.35 * 10-51 /s 
E) 8.22 * 1014 /s

Question 18

Which of the following is the electron configuration of an excited state of a copper atom?

Accepted Answer

A) [Ar]4s23d9 
B) [Ar]4s13d10 
C) [Ar]4s13d8 
D) [Ar]4s23d8 
E) [Ar]4s03d10 
A) [Ar]4s23d9 
B) [Ar]4s13d10 
C) [Ar]4s13d8 
D) [Ar]4s23d8 
E) [Ar]4s03d10

Question 19

If we take away two electrons from the outer shell of calcium, it would have the same electron configuration as what element?

Accepted Answer

The answer of If we take away two electrons from...

Question 20

The orbital diagram for a ground-state nitrogen atom is

Accepted Answer

A)    
B)    
C)    
D)    
A)    
B)    
C)    
D)

Exam 7: The Electronic Structure of Atoms

A ground-state chromium atom has how many unpaired electrons?

Calculate the wavelength, in nanometers, of the light emitted by a hydrogen atom when its electron falls from the n = 7 to the n = 4 principal energy level. Recall that the energy levels of the H atom are given by En = -2.18 * 10-18 J(1/n2)

Calculate the frequency of the light emitted by a hydrogen atom during a transition of its electron from the n = 6 to the n = 3 principal energy level. Recall that for hydrogen En = -2.18 * 10-18 J(1/n2).

A ground-state atom of iron has ___ unpaired electrons and is _____.

A photon is roughly 1800 times more massive than an electron. If a proton and an electron have the same kinetic energy,

Which one of the following sets of quantum numbers is not possible?

Which ground-state atom has an electron configuration described by the following orbital diagram?

The electron configuration of a ground-state Co atom is

The electron in a hydrogen atom falls from an excited energy level to the ground state in two steps, causing the emission of photons with wavelengths of 1870 and 102.5 nm. What is the quantum number of the initial excited energy level from which the electron falls?

Which of the following is the electron configuration of an excited state of an iron atom?

Calculate the wavelength associated with a 20Ne+ ion moving at a velocity of 2.0 * 105 m/s. The atomic mass of Ne-20 is 19.992 amu.

Calculate the wavelength of a neutron that has a velocity of 250 cm/s. (The mass of a neutron = 1.675 * 10-24 g; h = 6.626 * 10-34 J.s)

What is the binding energy (in J/mol or kJ/mol)of an electron in a metal whose threshold frequency for photoelectrons is 2.50 * 1014 /s?

According to de Broglie's equation, the wavelength associated with the motion of a particle increases as the particle mass decreases.

The ground-state electron configuration of Cr, Mo, and Ag are exceptions to the Aufbau principle. Which of the following is the electron configuration for Mo?

Calculate the frequency of the light emitted by a hydrogen atom during a transition of its electron from the n = 4 to the n = 1 principal energy level. Recall that for hydrogen En = -2.18 * 10 -18 J(1/n2)

Which of the following is the electron configuration of an excited state of a copper atom?

If we take away two electrons from the outer shell of calcium, it would have the same electron configuration as what element?

The orbital diagram for a ground-state nitrogen atom is

Introduction

Atoms, Molecules, and Ions

Stoichiometry

Reactions in Aqueous Solution

Gases

Energy Relationships in Chemical Reactions

The Periodic Table

Chemical Bonding I: the Covalent Bond

Chemical Bonding Ii: Molecular Geometry and Hybridization of Atomic Orbitals

Introduction to Organic Chemistry

Intermolecular Forces and Liquids and Solids

Physical Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Acid-Base Equilibria and Solubility Equilibria

Thermodynamics

Redox Reactions and Electrochemistry

The Chemistry of Coordination Compounds

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Calculate the wavelength, in nanometers, of the light emitted by a hydrogen atom when its electron falls from the n = 7 to the n = 4 principal energy level. Recall that the energy levels of the H atom are given by E_n = -2.18 * 10^-18 J(1/n²)

Calculate the frequency of the light emitted by a hydrogen atom during a transition of its electron from the n = 6 to the n = 3 principal energy level. Recall that for hydrogen E_n = -2.18 * 10^-18 J(1/n²).

A ground-state atom of iron has _ unpaired electrons and is ___.

Calculate the wavelength associated with a ²⁰Ne⁺ ion moving at a velocity of 2.0 * 10⁵ m/s. The atomic mass of Ne-20 is 19.992 amu.

Calculate the wavelength of a neutron that has a velocity of 250 cm/s. (The mass of a neutron = 1.675 * 10^-24 g; h = 6.626 * 10^-34 J.s)

What is the binding energy (in J/mol or kJ/mol)of an electron in a metal whose threshold frequency for photoelectrons is 2.50 * 10¹⁴/s?

Calculate the frequency of the light emitted by a hydrogen atom during a transition of its electron from the n = 4 to the n = 1 principal energy level. Recall that for hydrogen E_n = -2.18 * 10^-18 J(1/n²)