CHEM111 : 3.1, 3.2, 3.4, 3.6
joule J
The SI unit of energy is the _____ , which is abbreviated by the symbol _____.
False
True or False: The atomic orbital of the quantum mechanical model is very similar to the orbit described by the Bohr model.
- An s orbital has a spherical shape. - A 2s orbital has two regions of higher electron density.
Which of the following statements correctly describe an s orbital? Select all that apply. Multiple select question. - A 2s orbital has two regions of higher electron density. - s orbitals always occur in pairs. - An s orbital has a spherical shape. - An s orbital can have an mℓ value = 1.
- E = hν
Which of the following correctly reflects the relationship between energy and frequency? Multiple choice question. - E = hλ - E = h / v - E = v / h - E = hν
- 2, figure 8
A p orbital has _____ regions or lobes of high electron probability, on either side of the nucleus. This gives the orbital a(n) _____ shape. Multiple choice question. - 1, spherical - 1, figure 8 - 2, figure 8 - 2, spherical
levels orbit higher
According to the Bohr model for the hydrogen atom, the energy of the atom is not continuous but has certain discrete energy _____, each of which is related to a fixed circular _____ of the electron around the nucleus. The farther the electron is from the nucleus, the ____ the energy of the system.
- ground, excited
An atom is in its lowest energy state, or _____ state when its electrons are in the lowest possible energy levels. If an electron in the atom absorbs a photon of radiation that is equal in energy to the difference between two energy states it will move to a higher energy state, causing the atom to be in an _____ state. Multiple choice question. - excited, ground - maximized, minimized - ground, excited - minimized, maximized
- ^E = 3.03 x 10^-19 J -> ^E = hc/wavelength and remember to convert nm to m. - It moves to n = 2 -> a photon is emitted, so the value of n will decrease
An electron in the n = 3 energy level of the hydrogen atom emits a photon with wavelength 656.27 nm. What is the change in energy of the electron, and to which energy level does it move? - It moves to n = 4 - ^E = 3.03 x 10^-19 J - It moves to n = 1 - ^E = 3.03 x 10^-28 J - It moves to n = 2
line spectrum of hydrogen
An emission spectrum showing discrete, specific wavelengths is called a _____. Multiple choice question. - continuous spectrum - photon flurry - line spectrum - spectral absorption
line spectrum
An emission spectrum showing discrete, specific wavelengths is called a _____. Multiple choice question. - continuous spectrum - photon flurry - spectral absorption - line spectrum
- s, spherical, 1
An orbital with ℓ = 0 is called a(n) _____ type orbital and has a(n) _____ shape. There is always a total of _____ orbital(s) of this type for each principal energy level. Multiple choice question. - s, spherical, 3 - s, spherical, 1 - p, dumbbell, 3 - p, spherical, 3
difference
Atoms, like all other matter, have specific energy levels within them. For an atom to absorb radiation, the energy of the radiation must match the energy _____ between the two energy levels in the atoms.
- The wavelength of a line in the atomic line spectrum for hydrogen - The difference in energy between two energy levels in a hydrogen atom - The energy needed to remove an electron completely from the hydrogen atom
Bohr developed an equation for calculating the energy levels of a hydrogen atom. Which of the following can be determined using this equation? Select all that apply. Multiple select question. - The wavelength of a line in the atomic line spectrum for hydrogen - The difference in energy between two energy levels in a hydrogen atom - The absolute energy of the hydrogen atom in its ground state - The energy needed to remove an electron completely from the hydrogen atom
Use equation c = λv to convert wavelength to frequency, then use equation E = hv to determine the energy of the photon for each wavelength. The wavelengths must be converted from nanometers to meters: 600. nm x (1 x 10^-9 m / 1 nm) = 6.00 x 10^-7 m Then frequency(v) = (speed of light(c) / wavelength(λ) = (3.00 x 10^8 m/s) / (6.00 x 10^-7m) = 5.00 x 10^-14 s^-1 Then Energy = (Planck's constant)x(frequency) = (6.63 x 10^-34 J*s)x(5.00 x 10^-14 s^-1) Answer = 3.32 x 10^-19 J
Calculate the energy of a photon of orange light with a wavelength of 600. nm. Multiple choice question. - 3.32 × 10-28 - 3.98 × 10-31 J - 3.98 × 10-40 J - 3.32 × 10-19 J
We must convert the wavelength to meters and solve for frequency using (the speed of light = (wavelength)(frequency)) Rearranging the equation to solve for frequency gives frequency = (speed of light) / (wavelength) The speed of light is 3.00 x 10^8 m/s Wavelength > meters = 83.5 nm x (1 x 10^-9 m / 1 nm) = 8.35 x 10^-8 m Solution -> frequency = (3.00 x 10^8 m/s) / (8.35 x 10^-7) = 3.59 x 10^15 s^-1
Determine the frequency (in s−1) of radiation with a wavelength of 83.5 nm. Multiple choice question. - 3.59 × 1015 s−1 - 25.1 s−1 - 2.78 × 10−16 s−1 - 3.59 × 106 s−1
ultraviolet 97.3 nm Reason: 1/λ = (2.18x10^-18 J) / (6.63x10^-34J)(3.00x10^8 m/s) ((1/12) - (1/42) = 1.03 x 10^7 m^-1 λ = (1.03 x 10^-7 m^-1)^-1 = 9.73 x 10^-8 m
Determine the wavelength of radiation emitted when the electron in a hydrogen atom moves from n = 4 to n = 1. In what region of the electromagnetic spectrum does this emission occur? Multiple select question. - visible - radio - 122 nm - 97.3 nm - X-ray - 487 nm - ultraviolet - 1.03 × 107 m
energy difference
Each element has its own atomic line spectrum, consisting of fine lines of individual wavelengths that are characteristic of the element. This occurs because the atom contains specific _____ levels, and an atom can only absorb or emit radiation that corresponds to the energy _____between these levels.
photons frequency
Electromagnetic radiation consists of particles called _____, which are characterized by a specific wavelength and _______.
- quantum; frequency
Energy is not continuous, but is quantized or divided into "packets," each of which contains a definite amount of energy. An energy packet is called a(n) _____, and the energy of each packet is directly proportional to its _____. Multiple choice question. - quantum; wavelength - quantum; frequency - blackbody; frequency - blackbody; wavelength
- There is a basic unit of energy that cannot be subdivided further.
Energy is quantized. What does this mean? Multiple choice question. - Energy can be measured. - Energy can be absorbed or emitted in any quantity. - There is a fixed quantity of energy in the universe. - There is a basic unit of energy that cannot be subdivided further.
- energy and frequency
If a solid object is heated to a high enough temperature it will begin to glow. The color of light it emits depends on the temperature. This relationship between color and temperature implies a relationship between _____. Multiple choice question. - frequency and wavelength - energy and amplitude - energy and frequency
- energy; closer; lower
In Bohr's model of the atom, the quantum number n is associated with the _____ of an electron orbit. The lower the n value, the _____ the electron is to/from the nucleus and the _____ the energy level. Multiple choice question. - orientation; closer; lower - orientation; farther; higher - energy; farther; higher - energy; closer; lower
wave orbital
In the quantum mechanical model of the atom, an electron is viewed as a particle-wave occupying a three-dimensional space near the nucleus. This space is modeled by the _____ function (Ψ) in the Schrodinger equation. The different functions of Ψ are also called atomic _____, each with a characteristic energy and distribution of electron density.
Wavelength -><- The distance between successive identical points of a wave Frequency -><- The number of waves that pass through a point in 1 sec. Amplitude - ><- The vertical distance between the midline of a wave an the top of its peak
Match each property of a wave to the correct definition. Wavelength -> Frequency -> Amplitude - > <- The number of waves that pass through a point in 1 sec. <- The distance between successive identical points of a wave <- The vertical distance between the midline of a wave an the top of its peak
X rays -><- medical diagnosis ultraviolet -><- sun lamps infrared -><- heat lamps microwave -><- cell phones
Match each region of the electromagnetic spectrum with a practical application. X rays -> ultraviolet -> infrared -> microwave -> <- sun lamps <- cell phones <- heat lamps <- medical diagnosis
Chemical energy-><- Energy stored in the structure of compound Electrostatic energy -><- Energy resulting from the interaction of charged particles Thermal energy-><- Energy associated with the random motion of atoms and molecules Kinetic energy -><- Energy that results from motion Potential energy -><- Energy possesed by an object due to its position
Match each type of energy with the correct definition. Chemical energy-> Electrostatic energy -> Thermal energy-> Kinetic energy -> Potential energy -> <- Energy resulting from the interaction of charged particles <- Energy stored in the structure of compound <- Energy associated with the random motion of atoms and molecules <- Energy possesed by an object due to its position <- Energy that results from motion
f orbitals occur in groups of -><- 7 d orbitals occur in groups of -><- 5 d orbitals are possible when ->< - n > or = 3 f orbitals are possible when -><- n > or = 4
Match each type of orbital with the correct description. f orbitals occur in groups of -> d orbitals occur in groups of -> d orbitals are possible when -> f orbitals are possible when -> <- n > or = 4 <- 5 < - n > or = 3 <- 7
450 nm -><- 6.67 x 10^14 s^-1 600 nm -><- 5.00 x 10^14 s^-1 750 nm -><- 4.00 x 10^14 s^-1 850 nm -><- 3.53 x 10^14 s^-1
Match each wavelength with its associated frequency. (Hint: you should be able to answer this problem without a calculator if you consider the relationship between wavelength and frequency!) 450 nm -> 600 nm -> 750 nm -> 850 nm -> <- 5.00 x 10^14 s^-1 <- 6.67 x 10^14 s^-1 <- 3.53 x 10^14 s^-1 <- 4.00 x 10^14 s^-1
- X ray - UV radiation - Visible light - IR radiation - Radio Waves
Place the following types of electromagnetic radiation in order of increasing wavelength (shortest at the top to longest at the bottom). - UV radiation - Radio Waves - X ray - IR radiation - Visible light
1. Q1 = -2; Q2 = +1 = - 2 2. Q1 = -3; Q2 = +1 = - 3 3. Q1 = -2; Q2 = +2 = - 4 4. Q1 = -2; Q2 = +3 = - 6
Rank the following in order of increasing energies of attraction (with the weakest interaction located at the top of the list) based on the interaction of electric charges when a particle with charge Q1 interacts with another particle with charge Q2. Assume that the distance between charges is the same in each case. - Q1 = -2; Q2 = +1 - Q1 = -2; Q2 = +2 - Q1 = -3; Q2 = +1 - Q1 = -2; Q2 = +3
- Q1 = -2; Q2 = +1; d = 1.5 = - 1.3333... - Q1 = -2; Q2 = +2; d = 2.2 = - 1.8181... - Q1 = -1; Q2 = +1; d = 0.5 = - 2 - Q1 = -3; Q2 = +2; d = 2.5 = - 2.4
Rank the following in order of increasing energies of attraction (with the weakest interaction located at the top of the list) based on the interaction of electric charges when a particle with charge Q1 is separated by a relative distance d from another particle with charge Q2. - Q1 = -2; Q2 = +2; d = 2.2 - Q1 = -1; Q2 = +1; d = 0.5 - Q1 = -2; Q2 = +1; d = 1.5 - Q1 = -3; Q2 = +2; d = 2.5
- X rays - visible light - radio waves
Rank the following in order of increasing wavelength, with the smallest wavelength at the top of the list. - visible light - X rays - radio waves
- The energy needed to remove an electron completely from a hydrogen atom - The frequency of a line in the line spectrum for hydrogen
Select the quantities that can be calculated using Bohr's equation. Select all that apply. Multiple select question. - The wavelength of a line in the line spectrum for any atom - The frequency of a line in the line spectrum for hydrogen - The difference in energy between two energy levels in any atom - The energy needed to remove an electron completely from a hydrogen atom
- the product of the two charges; the distance between the two charges
The electrostatic energy between two charged particles may be calculated using an equation which shows Eel to be directly proportional to _____ and indirectly proportional to _____. Multiple choice question. - the distance between the two charges; the sum of the two charges - the sum of two charges; the square root of the distance between the charges - the product of the two charges; the distance between the two charges - the product of the two charges; the square of the distance between the charges
- principal, increases
The energies of the orbitals in hydrogen depend only on the value of the ______ quantum number. The energy of the orbital ______ as this quantum number increases. Multiple choice question. - principal, decreases - major, increases - principal, increases - major, decreases
Energy of a photon = (Planck's constant)x(frequency of the light) Energy of a photon = (6.63 x 10^-34 J*s)x(1.0 x 10^15 s^-1) Answer = 6.6 x 10^-19
The energy of a photon with a frequency of 1.0 x 1015 s-1 is equal to ______ J. h = 6.63 x 10-34 J⋅s. Multiple choice question. - 1.5 x 1048 - 1.5 x 1018 - 6.6 x 10-19 - 6.6 x 10-53
- proportional to; proportional to the square of Reason: Ek = 1/2 mu^2
The kinetic energy of an object may be calculated using an equation which shows Ek to be _____ the object's mass and _____ the object's velocity. Multiple choice question. - proportional to; proportional to the square of - proportional to the square of; indirectly proportional to the square of - indirectly proportional to the square of; proportional to - indirectly proportional to; proportional to
conservation
The law of _______ of energy states that energy can be neither created nor destroyed.
- principal; angular momentum
The relative energies of the orbitals in the hydrogen atom depend on the value of the ______ quantum number but not on the value of the _____ quantum number. Multiple choice question. - angular momentum; principal - angular momentum; magnetic - principal; angular momentum - principal; magnetic
frequency light
The speed of a wave is determined by multiplying the ____of the wave by its wavelength. In a vacuum, all electromagnetic radiation travels at a constant speed, the speed of ____, which is equal to 3.00 x 108 m/s. (Include a word in the last fill-in-the-blank space, not a symbol or number.)
True
True or false: Bohr's theory explains the line spectrum of hydrogen but cannot explain the spectra of other atoms.
True - Heat and work are both forms of energy, and the joule is the SI unit of energy.
True or false: Both heat and work can be measured in joules.
electromagnetic wave
Visible light forms a small part of the _____ spectrum, which includes other types of radiation. All radiation exhibits _____-like behavior.
- inversely; decrease
Wavelength and frequency are _____ proportional to each other. As wavelength increases, frequency will _____. Multiple choice question. - inversely; increase - inversely; decrease - directly; increase - directly; decrease
- energy
When solids are heated sufficiently they emit colors. The color distribution of the emitted radiation depends on temperature; an object glowing red is cooler than one glowing blue. This phenomenon illustrates a relationship between the frequency of the emitted radiation and the _____ given off by the object. Multiple choice question. - color - wavelength - energy - electrons
- A mathematical function that describes the position of the electron wave in three dimensions
Which of the following correctly defines an atomic orbital in terms of the quantum mechanical model of the atom? Multiple choice question. - A well-defined three-dimensional space occupied by an electron of a particular energy - A fixed orbit or circular pathway that an electron of a particular energy follows - A mathematical function that describes the position of the electron wave in three dimensions - A wave function that defines a region of probability of finding an electron of a particular energy
E = hν E = hc / λ -> Reason: Since c = λv , v = c / λ , thus E = hc / λ
Which of the following correctly expresses energy in terms of Planck's constant? Select all that apply. Multiple select question. E = hν E = hc / λ E = h / v E = h / cv E = Rν
- The lowest energy state of an atom, where all electrons are in the lowest energy levels possible
Which of the following defines the ground state of an atom? Multiple choice question. - The lowest energy state of an atom, where all electrons are in the lowest energy levels possible - The energy state of an atom that has formed stable bonds - An atom that has reached a low-energy state by gaining or losing electrons - The energy state of an atom when it has a full valence shell of electrons
- The wavelength of a wave is the distance between two successive peaks or troughs. - Frequency is represented by the symbol ν. - The units of frequency are s-1.
Which of the following options correctly describe the parameters that define waves? Select all that apply. Multiple select question. - Wavelength is represented by the symbol ω. - Frequency is represented by the symbol ν. - The amplitude of a wave is the vertical distance from the peak of a wave to its trough. - The units of frequency are s-1. - The wavelength of a wave is the distance between two successive peaks or troughs.
- The Bohr model cannot account for the behavior of multielectron species.
Which of the following options correctly describes the limitations of the Bohr model of the atom? Multiple choice question. - The Bohr model does not account for the existence of a nucleus. - The Bohr model cannot account for the behavior of multielectron species. - The Bohr model cannot explain the existence of atomic line spectra. - The Bohr model cannot explain how atoms emit or absorb energy.
Electrostatic energy is potential energy that results from the interaction of charged particles. Oppositely charged particles attract each other, and particles of like charges repel each other. The magnitude of the resulting electrostatic potential energy is proportional to the product of the two charges (Q1 and Q2) divided by the distance between them (d). Eel ∝ (Q1 Q2 / d)
Which of the following properly shows the electrostatic energy (Eel) resulting from the interaction of two charged particles (Q1 and Q2) over a distance (d)? Multiple choice question. - Eel ∝ d / Q1 Q2 - Eel ∝ Q1Q2d - Eel ∝ (Q1 Q2 / d) - Eel ∝ (Q1 d / Q2)
- A photon is a particle of electromagnetic radiation. - Matter cannot absorb or emit a fraction of a photon.
Which of the following statements correctly describe a photon? Select all that apply. Multiple select question. - A high-frequency photon has low energy. - All photons have the same amount of energy. - A photon is a particle of electromagnetic radiation. - Matter cannot absorb or emit a fraction of a photon.
- Each element has its own unique atomic line spectrum. - An atomic line spectrum arises from the emission of light of specific wavelengths. - Atomic line spectra include radiation outside the visible range of the electromagnetic spectrum.
Which of the following statements correctly describe atomic line spectra? Select all that apply. Multiple select question. - An atom emits radiation continuously to produce a line spectrum. - An atom emits radiation that contains all wavelengths of the electromagnetic spectrum. - An atomic line spectrum arises from the emission of light of specific wavelengths. - Atomic line spectra include radiation outside the visible range of the electromagnetic spectrum. - Each element has its own unique atomic line spectrum.
- d orbitals are only possible for n ≥ 3. - d orbitals always occur in sets of 5.
Which of the following statements correctly describe d orbitals? Select all that apply. Multiple select question. - d orbitals always occur in sets of 5. - d orbitals are only possible for n ≥ 3. - The d orbitals within the same shell may have different energies. - The d orbitals within the same shell all have the same shape.
- The kinetic energy of an object is directly proportional to its mass. - Changes in thermal energy are detected by measuring temperature changes. - Chemical energy is a type of potential energy.
Which of the following statements correctly describe different types of energy? Select all that apply. Multiple select question. - The kinetic energy of an object is directly proportional to its mass. - Electrostatic energy arises from the movement of charged particles. - Changes in thermal energy are detected by measuring temperature changes. - The potential energy of an object is directly proportional to its speed. - Chemical energy is a type of potential energy.
- p orbitals always occur in groups of three. - A p orbital has a dumbbell shape with two lobes, one on either side of the nucleus. - The p orbitals of a group are perpendicular to each other.
Which of the following statements correctly describe p orbitals? Select all that apply. Multiple select question. - A p orbital has a dumbbell shape with two lobes, one on either side of the nucleus. - A p orbital has its highest electron density at the nucleus. - The p orbitals of a group have different shapes and energies. - p orbitals always occur in groups of three. - The p orbitals of a group are perpendicular to each other.
- Each energy state of the hydrogen atom is associated with a fixed circular orbit of the electron around the nucleus. - Only certain energy levels are allowed within the hydrogen atom. - The atom is in its lowest energy state when the electron is in the orbit closest to the nucleus.
Which of the following statements correctly describe the Bohr model of the hydrogen atom? Select all that apply. Multiple select question. - The atom is in its lowest energy state when the electron is in the orbit closest to the nucleus. - The atom is in an excited state when the electron is in the orbit closest to the nucleus. - Only certain energy levels are allowed within the hydrogen atom. - The electron can move to a higher energy state by absorbing a photon with energy equal to that of the new energy state. - Each energy state of the hydrogen atom is associated with a fixed circular orbit of the electron around the nucleus.
- Each electron occupies a three-dimensional space near the nucleus. This space is described by a wave function. - The electron density in the atom can be described by wave functions. - Electrons exhibit behavior of both waves and particles.
Which of the following statements correctly describe the atom in terms of quantum mechanics? Select all that apply. Multiple select question. - An electron may be precisely located within an atom if we know which atomic orbital it is in. - Each electron occupies a three-dimensional space near the nucleus. This space is described by a wave function. - The electron density in the atom can be described by wave functions. - Electrons exhibit behavior of both waves and particles. - Electrons have certain allowed energy states associated with fixed orbits around the nucleus.
- The energy of the absorbed radiation must match the difference between the two energy states of the atom.
Which of the following statements correctly describes how energy is absorbed by an atom? Multiple choice question. - The energy of the absorbed radiation must be greater than the difference between the two energy states of the atom. - The energy of the absorbed radiation must match the difference between the two energy states of the atom. - The atom will keep absorbing more energy until the total amount absorbed equals the energy difference between the two energy states in the atom.
- Energy can be converted from one form to another. - Energy can neither be created nor destroyed.
Which of the following statements correctly reflect the law of conservation of energy? Select all that apply. Multiple select question. - One form of kinetic energy must always be transformed into a different type of kinetic energy. - Energy is lost when an object slows down. - The total energy of the universe is constantly decreasing. - Energy can be converted from one form to another. - Energy can neither be created nor destroyed.
- n indicates the energy level of an electron in the atom. - An electron with n = 2 is at higher energy than an electron with n = 1. - n can have any positive, whole-number value greater than or equal to 1.
Which statement correctly describes the quantum number n with reference to the Bohr model of the hydrogen atom? Select all that apply. Multiple select question. - The higher the value of n, the closer the electron is to the center of the atom. - n indicates the energy level of an electron in the atom. - n can have any positive, whole-number value greater than or equal to 1. - An electron with n = 2 is at higher energy than an electron with n = 1. - n is a measure of the difference in energy between two energy levels.
