Chapter 11: Modern Atomic Theory

Question 1

The form of electromagnetic radiation that has less energy per photon than infrared rays but more energy per photon than radio waves is:

A. microwaves
B. ultraviolet
C. gamma rays
D. X rays

Answer 1

A – Microwaves

Question 2

How many electrons can be contained in all of the orbitals with a principal energy level of 3 (n = 3)?

A.8
B. 10
C. 18
D. 32

Answer 2

C – 18

Question 3

In general, the rows on the periodic table correspond to and the columns numbered 1A, 2A, . . . 8A correspond to ___________________.

A. the orbital of the valence electrons; the number of total electrons

B. the energy level of the valence electrons; the number of valence electrons

C. the energy level for the core electrons; the orbital of the valence electrons

D. the number of valence electrons: the energy level of the valence electrons

Answer 3

B – the energy level of the valence electrons; the number of valence electrons

Question 4

An orbital is best described as

A. the pathway for an electron.

B. a region of probability of finding an electron.

C. the space in which only valence electrons exist.

D.a physical structure that holds the electrons.

Answer 4

B – a region of probability of finding an electron

Question 5

Which of the following is true about the trend of ionization energy across a row on the periodic table?

A. Ionization energy generally increases to the right because the number of protons increases from left to right.

B. Ionization energy generally decreases to the right because the number of electrons increases from left to right.

C. Ionization energy generally decreases to the right because the number of protons increases from left to right.

D. Ionization energy is constant since all atoms in a row have the same valence energy level.

Answer 5

A – Ionization energy generally increases to the right because the number of protons increases from left to right.

Question 6

Which of the following is a representation of a p orbital?

Answer 6

C

Question 7

For the atoms Li, N, F, and Na, which of the following is the correct order from smallest to largest atomic radius?

A. Na, F, N, Li

B. Na, Li, N, F

C. N, F, Na, Li

D. F, N, Li, Na

Answer 7

D –

F, N, Li, Na

Question 8

Which of the following correctly ranks the ionization energies of O, F, Na, S, and Cs from smallest to largest?

A. Cs, Na, S, O, F

B. Cs, S, Na, O, F

C. F, O, Na, S, Cs

D. F, O, S, Na, Cs

Answer 8

A –

Cs, Na, S, O, F

Question 9

Write the expected electron configuration for the ground state of iron.

Answer 9

Question 10

Fill in the following orbital diagram for a ground state oxygen atom.

Answer 10

Question 11

Fill in the following orbital diagram for a boron atom in an excited state.

Answer 11

Question 12

True or false?

Across a row of the periodic table, smaller atoms generally have smaller ionization energies.

If true, provide an example and explain your answer.

If false, provide a counterexample and explain your answer.

Answer 12

False.

In general, atoms tend to get smaller (have smaller radii) across a row because the number of protons increases, thus increasing the pull on the electrons. Because of this, smaller atoms in the same row tend to have larger ionization energies (more energy is required to remove an electron). For example, fluorine (F) is smaller than lithium (Li) and has a higher ionization energy.

Question 13

Rutherford’s Atom:

Nuclear Model of the Atom has a small, dense nucleus that:

– is _____________ charged

– contains _____________ (+1 charge)

– contains _____________ (no charge)

The remainder of the atom:

– is mostly ________________.

– contains ____________ (-1 charge)

Answer 13

is POSITIVELY charged

contains PROTONS

contains NEUTRONS

is mostly EMPTY SPACE

contains ELECTRONS

Question 14

electromagnetic radiation is one of the ways that energy travels through space.

What are three characteristics of Electromagnetic Radiation

Answer 14

1. Wavelength
2. Frequency
3. Speed

Question 15

Describe how atoms emit light:

They first must receive _______________ and become ____________.

The ______________ is released in the form of a ____________.

Answer 15

They first must receive ENERGY and become EXCITED.

The ENERGY is released in the form of a PHOTON.

Question 16

Define the 2 Atomic States: Excited & Ground

What happens to the energy levels of hydrogen?

Describe how the emission spectrum of hydrogen demonstrates the quantized nature of energy.

Answer 16

Excited: atom with excess energy

Ground: atom in lowest possible state.

Energy in the photon corresponds to the energy used by the atom to get to the excited state.

Quantized energy level because only certain energy changes occur, the H atom must contain discrete energy levels.

Question 17

The Energy Levels of Hydrogen:

Energy can be gained or lost on in _____________ of hv.

A system can transfer energy only in ____________.

Energy seems to have _______________ properties.

Answer 17

Energy can be gained or lost only in Interger Multiples of hv.

A system can transfer energy only in Whole Quanta (or packets).

Energy seems to have Particulate Properties

Question 18

Describe 3 main concepts of Bohr’s model of the hydrogen atom

Answer 18

1. Quantized energy levels
2. Electron moves in a circular orbit
3. Electron jumps between levels by absorbing or emitting a photon of a particular wavelength

Question 19

What’s the deal with Bohr? was the model proven? or was it incorrect? Why?

Answer 19

Bohr’s model of the atom was incorrect. Electrons do not move in a circular orbit.

Question 20

Identify the shapes of the s, p, and d orbitals

Answer 20

Question 21

Explain how the electron’s position is represented in the wave mechanical model

Question 22

Summarize the energy levels and orbitals of the wave mechanical model of the atom

Question 23

Describe how the principal energy levels fill with electrons in atoms beyond hydrogen

Answer 23

They need one more property to determine how the electrons are arranged.

Electrons Spin can have one of two values, represented with an UP or DOWN arrow.

The Pauli Exclusion Principle:

An atomic orbital can hold a maximum of 2 electrons

The 2 electrons must have opposite spin.

Question 24

List the electron configurations of atoms with we said in class through Ba (56) no F block stuff but be able to do s,p,d

Answer 24

Question 25

Compare valence electrons and core electrons

Answer 25

Valence: electrons in the outermost (highest) principal energy level of an atom

Core: inner electrons

Elements with the same valence electron arrangement show very similar chemical behavior

Question 26

List the electron configurations of atoms with we said in class through Ba (56) no F block stuff but be able to do s,p,d CONTINUED

Answer 26

Question 27

Analyze the general trends in properties in the
periodic table (atomic size?)

Moving Left to Right Atomic Size ___________.

Effective nuclear charge __________, therefore the valence electrons are ____________ to the nucleus, ________________ the size of the atom.

Atomic Size ______________ going down a group.

Orbital sizes ____________ in successive principal quantum levels.

Answer 27

Moving Left to Right Atomic Size DECREASES

Effective nuclear charge INCREASES; therfore the valence electron are DRAWN CLOSER to the nucleus, DECREASING the size of the atom.

Atomic size INCREASES going down a group.

Orbital sizes INCREASE in successive principal quantum levels.