quantum theory

energy

An electron for which n = 4 has more ____ than an electron for which n = 2. a. spin c. energy b.particle nature d. wave nature

inversely proportional to its frequency.

Because c, the speed of electromagnetic radiation, is a constant, the wavelength of the radiation is a. proportional to its frequency. b. equal to its frequency. c. inversely proportional to its frequency. d. double its frequency.

frequency

The energy of a photon is related to its a. mass. c. frequency. b.speed. d. size.

s2, p6, d10, f14

The letter designations for the first four sublevels with the maximum number of electrons that can be accommodated in each sublevel are a. s:2, p:4, d:6, and f:8. b. s:1, p:3, d:5, and f:7. c. s:2, p:6, d:10, and f:14. d. s:1, p:2, d:3, and f:4.

5

The number of orbitals for the d sublevel is a. 1. c. 5. b. 3. d. 7.

0,1

What values can the angular momentum quantum number have when n = 2? a. +1/2, -1/2 b. -1/2, -1, -2 c. 0, 1, 2 d. 0, 1

lyman series

Which is not part of hydrogen's line-emission spectrum? a. Balmer series. c. Lyman series. b.Aufbau series. d. Paschen series.

Quantum theory

describes mathematically the wave properties of electrons and other very small particles

speed=frequency x wavelength

equation for speed of a wave

f

flower shaped, 7 orbitals, 14 electrons

orbital (orientation in space)

magnetic QN tells us

s

spherical, 1 orbital, 2 electrons

Heisenberg uncertainty principle

states that it is impossible to determine simultaneously both the position and velocity of an electron or any other particle

Spin quantum number

symbolized by s, has only two possible values- ⁺1/2 and ⁻1/2 which indicate the two fundamental spin states of an electron in an orbital

Electron configuration

the arrangement of electrons in an atom

Ground state

the lowest energy state of an atom

Quantum

the minimum quantity of energy that can be lost or gained by an atom

Frequency

the number of waves that pass a given point in a specific time

Dual nature of light! (wave + particle)

what did Einstein contribute?

First observed photoelectric effect: shining light of the right frequency level on an element, electrons will jump out of the atoms Explained by the fact that light is a particle (photons) Unit for frequency called Hertz

what did Hertz contribute?

Energy of photon= constant x frequency->different than speed of wave = wavelength x frequency

what did Planck contribute?

You cannot KNOW what something WAS- only what it is now Cat in box- could have been alive or dead, regardless of what it is now, but you'll never know EQUATIONS: electrons as waves

what did Schrödinger contribute?

Double slit experiment => light must be made of waves

what did Young contribute?

Electrons also = particles AND waves

what did deBroglie contribute?

1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p, 6f, 7d, 7f

what is the order of filling?

d

double peanut shaped, 5 orbitals, 10 electrons

released photons of only certain energies

Because excited hydrogen atoms always produce the same line-emission spectrum, scientists concluded that hydrogen a. had no electrons. b. did not release photons. c. released photons of only certain energies. d. could only exist in the ground state.

3d1, 4s2

In the electron configuration for scandium (atomic number 21), what is the notation for the three highest-energy electrons? a. 3d1 4s2 c. 3d3 b. 4s3 d. 4s2 4p1

electrons should be considered as waves confined to space around an atomic nucleus

Louis de Broglie's research suggested that a. frequencies of electron waves do not correspond to specific energies. b. electrons usually behave like particles and rarely like waves. c. electrons should be considered as waves confined to the space around an atomic nucleus. d. electron waves exist at random frequencies.

wavelength

The distance between two successive peaks on adjacent waves is its a. frequency. c. quantum number. b.wavelength. d. velocity.

Excited state

a state in which an atom has a higher potential energy than it has in its ground state

f magnetic QN

ml=-3,-2,-1,0,1,2,3

s magnetic QN

ml=0

d magnetic QN

ml=2,-1,0,1,2

Photon

particle of EMR having zero mass and carrying a quantum of energy

energy level

principle QN tells us

it is similar to bohrs theory

All of the following describe the Schrödinger wave equation except a. it is an equation that treats electrons in atoms as waves. b. only waves of specific energies and frequencies provide solutions to the equation. c. it helped lay the foundation for the modern quantum theory. d.it is similar to Bohr's theory.

excited hydrogen gas gives off certain colors of light

Bohr's theory helped explain why a. electrons have negative charge. b.most of the mass of the atom is in the nucleus. c.excited hydrogen gas gives off certain colors of light. d.atoms combine to form molecules.

octet

If the s and p orbitals of the highest main energy level of an atom are filled with electrons, the atom has a(n) a. electron pair. c. empty d orbital. b.octet. d. electron in an excited state.

3

One main energy level can hold 18 electrons. What is n? a.1/2 c. 6 b. 3 d. 18

line emission spectrum

The Bohr model of the atom was an attempt to explain hydrogen's a. density. b.flammability. c. mass. d. line-emission spectrum.

5s

The atomic sublevel with the next highest energy after 4p is a. 4d. c. 5p. b. 4f. d. 5s.

hertz

The frequency of electromagnetic radiation is measured in waves/second, or a. nanometers. b.quanta. c. hertz. d. joules.

speed.

Visible light, X rays, infrared radiation, and radio waves all have the same a. energy. c. speed. b. wavelength. d. frequency.

Electromagnetic radiation

a form of energy that exhibits wavelike behavior

Line-emission spectrum

a series of specific wavelengths of the emitted light created when the visible portion of light from excited atoms is shined through a prism

photon

A quantum of electromagnetic energy is called a(n) a. photon. c. excited atom. b.electron. d. orbital.

2

A single orbital in the 3d level can hold ____ electrons. a. 10 c. 3 b. 2 d. 6

an s orbital

A spherical electron cloud surrounding an atomic nucleus would best represent a. an s orbital. b. a px orbital. c. a combination of px and py orbitals. d.a combination of an s and a px orbital.

orbital

A three-dimensional region around a nucleus where an electron may be found is called a(n) a. spectral line. c. orbital. b. electron path. d. orbit.

in specific allowed orbits

According to the Bohr model of the atom, the single electron of a hydrogen atom circles the nucleus a. in specific, allowed orbits. b. in one fixed orbit at all times. c. at any of an infinite number of distances, depending on its energy. d.counterclockwise.

the energy of the light is too low

According to the particle model of light, certain kinds of light cannot eject electrons from metals because a. the mass of the light is too low. b.the frequency of the light is too high. c. the energy of the light is too low. d. the wavelength of the light is too short.

an electrons position cannot be known precisely

According to the quantum theory of an atom, in an orbital a. an electron's position cannot be known precisely. b. an electron has no energy. c. electrons cannot be found. d.electrons travel around the nucleus on paths of specific radii.

it helps locate an electron in an atom

All of the following describe the Heisenberg uncertainly principle except a. it states that it is impossible to determine simultaneously both the position and velocity of an electron or any other particle. b. it is one of the fundamental principles of our present understanding of light and matter. c. it helped lay the foundation for the modern quantum theory. d. it helps to locate an electron in an atom.

Electromagnetic spectrum

All the forms of electromagnetic radiation

noble gas

An element with 8 electrons in its highest main energy level is a(n) a. octet element. c. Aufbau element. b. third period element. d. noble gas.

3f

An orbital that can never exist according to the quantum description of the atom is a. 3d. c. 6d. b.8s. d. 3f.

shape of an orbital

The angular momentum quantum number indicates the a. orientation of an orbital around the nucleus. b. shape of an orbital. c. direction of the spin of the electron in its orbital. d.main energy level of an orbital.

1s2 2s2 2p6 3s2 3p1

The electron notation for aluminum (atomic number 13) is a. 1s2 2s2 2p3 3s2 3p3 3d1. b. 1s2 2s2 2p6 3s2 2d1. c. 1s2 2s2 2p6 3s2 3p1. d.1s2 2s2 2p9.

how electron wave frequencies correspond to specific energies

The equation E = h helped Louis de Broglie determine a. how protons and neutrons behave in the nucleus. b. how electron wave frequencies correspond to specific energies. c. whether electrons behave as particles. d.whether electrons exist in a limited number of orbits with different energies.

principle quantum numbers

The main energy levels of an atom are indicated by the a. orbital quantum numbers. b. magnetic quantum numbers. c. spin quantum numbers. d. principal quantum numbers.

the 2s orbital is at a higher energy level

The major difference between a 1s orbital and a 2s orbital is that a. the 2s orbital can hold more electrons. b. the 2s orbital has a slightly different shape. c. the 2s orbital is at a higher energy level. d.the 1s orbital can have only one electron.

3

The number of possible different orbital shapes for the third energy level is a. 1. c. 3. b. 2. d. 4.

dumbbells

The p orbitals are shaped like a. electrons. c. dumbbells. b.circles. d. spheres.

angular momentum

l=0,1,2,3,

p magnetic QN

ml=-1,0,1

spin QN

ms=1/2, -1/2

principle QN

n=1,2,3,4

Pauli exclusion principle

no two electrons in the same atom can have the same set of four quantum numbers

Hund's rule

orbitals of equal energy are each occupied by one electron before any orbital is occupied by a second electron, and all electrons in singly occupied orbitals must have the same spin

p

peanut shaped, 3 orbitals, 6 electrons

Quantum numbers

specify the properties of atomic orbitals and the properties of electrons in orbitals

Angular momentum quantum number

symbolized by l, indicates the shape of the orbital

Magnetic quantum number

symbolized by m, indicates the orientation of an orbital around the nucleus

Principle quantum number

symbolized by n, indicates the main energy level occupied by the electron

Continuous spectrum

the emission of a continuous range of frequencies of electromagnetic radiation

Photoelectric effect

the emission of electrons from a metal when light shines on the metal

Orbital

3D region around the nucleus that indicates the probable location of an electron

hund's rule

"Orbitals of equal energy are each occupied by one electron before any is occupied by a second electron, and all electrons in singly occupied orbitals must have the same spin" is a statement of a. the Pauli exclusion principle. c. the quantum effect. b.the Aufbau principle. d. Hund's rule.

Certain energy levels an element can have!

1. what did Bohr do?

According to the Pauli exclusion principle, no two electrons can have the same set of four quantum numbers. Therefore, no more than two electrons can occupy an orbital, and these two must have opposite spins.

How does the figure above illustrate the Pauli exclusion principle?

According to Hund's rule, the arrangement of electrons with the maximum number of unpaired electrons is the most stable arrangement.

How does the figure below illustrate Hund's rule?

The 3 in 2p3 indicates that three electrons are in the p orbitals of the second energy level.

The electron configuration for nitrogen is 1s2 2s2 2p3. What does the 3 in 2p3 mean?

magnetic QN

ml= -1 to +1

direction of spin

spin QN tells us

1

How many orientations can an s orbital have about the nucleus? a. 1 c. 3 b. 2 d. 5

4

How many quantum numbers are needed to describe the energy state of an electron in an atom? a. 1 c. 3 b. 2 d. 4

ground state

If electrons in an atom have the lowest possible energies, the atom is in the a. ground state. b. inert state. c. excited state. d. radiation-emitting state.

2n^2

If n is the principal quantum number of a main energy level, the number of electrons in that energy level is a. n. c. n2. b. 2n. d. 2n2.

Wavelength

distance between corresponding points on adjacent waves

a reduction in the number of electrons in the 4s orbital and an increase in the 3d orbital.

Both copper (atomic number 29) and chromium (atomic number 24) appear to break the pattern in the order of filling the 3d and 4s orbitals. This change in pattern is expressed by a. an increase in the number of electrons in both the 3d and 4s orbitals. b. a reduction in the number of electrons in both the 3d and 4s orbitals. c.a reduction in the number of electrons in the 3d orbital and an increase in the 4s orbital. d. a reduction in the number of electrons in the 4s orbital and an increase in the 3d orbital.

energy must be absorbed

For an electron in an atom to change from the ground state to an excited state, a. energy must be released. b. energy must be absorbed. c. radiation must be emitted. d.the electron must make a transition from a higher to a lower energy level.

frequency times wavelength.

For electromagnetic radiation, c (the speed of light) equals a. frequency minus wavelength. b. frequency plus wavelength. c. frequency divided by wavelength. d. frequency times wavelength.

32

How many electrons are needed to completely fill the fourth energy level? a. 8 c. 32 b. 18 d. 40

two, if they have opposite spins

How many electrons can occupy the s orbitals at each energy level? a. two, if they have opposite spins b. two, if they have the same spin c. one d.no more than eight

speed of the wave.

The product of the frequency and the wavelength of a wave equals the a. number of waves passing a point in a second. b. speed of the wave. c. distance between wave crests. d. time for one full wave to pass.

magnetic quantum number

The quantum number that indicates the position of an orbital about the three axes in space is the a. principal quantum number. b. angular momentum quantum number. c. magnetic quantum number. d. spin quantum number.

electron cloud

The region outside the nucleus where an electron can most probably be found is the a. electron configuration. b.quantum. c. s sublevel. d. electron cloud.

the aufbau principle

The sequence in which energy sublevels are filled is specified by a. the Pauli exclusion principle. b. the orbital rule. c. Lyman's series. d. the Aufbau principle.

energy

The size and shape of an electron cloud are most closely related to the electron's a. charge. c. spin. b.mass. d. energy.

line emission spectrum

The specific wavelengths of light seen through a prism that are made when high-voltage current is passed through a tube of hydrogen gas at low pressure is a a. line-emission spectrum. b. electron configuration. c. photoelectric effect. d. continuous electromagnetic spectrum.

2

The spin quantum number indicates that the number of possible spin states for an electron in an orbital is a. 1. b. 2. c. 3. d. 5.

the direction of electron spin

The spin quantum number of an electron can be thought of as describing a. the direction of electron spin. b. whether the electron's charge is positive or negative. c. the electron's exact location in orbit. d.the number of revolutions the electron makes about the nucleus per second.

the aufbau principle

The statement that an electron occupies the lowest available energy orbital is a. Hund's rule. b.the Aufbau principle. c. Bohr's law. d. the Pauli exclusion principle.

the pauli exclusion principle

The statement that no two electrons in the same atom can have the same four quantum numbers is a. the Pauli exclusion principle. c. Bohr's law. b. Hund's rule. d. the Aufbau principle.

4

The total number of orbitals that can exist at the second main energy level is a. 2. c. 4. b. 3. d. 8.

the photoelectric effect

The wave model of light does not explain a. the frequency of light. b.the continuous spectrum c. interference. d. the photoelectric effect.

3 quantum numbers describe its location and the 4th describes its spin

What do quantum numbers describe?

1s 2s 2p 3s 3p 4s 3d 4p 5s

Which of the following lists atomic orbitals in the correct order they are filled according to the Aufbau principle? a. 1s 2s 2p 3s 4s 3p 3d 4p 5s b. 1s 2s 2p 3s 3p 4s 3d 4p 5s c. 1s 2s 2p 3s 3p 4s 4p 3d 4d d.1s 2s 2p 3s 3p 3d 4s 4p 5s

Aufbau principle

an electron occupies the lowest-energy orbital that can receive it

energy sublevel (orbital shapes)

angular momentum tells us