Chapter 7: Atomic Structure and Periodicity

Question 1

What is electromagnetic radiation

Answer 1

One of the means by which energy travels
through space

Question 2

fill in the blanks

Electromagnetic Radiation exhibits ________________ behavior, and travels at ________________________ in a vacuum

Answer 2

Exhibits wavelike behavior and travels at the speed of light in a vacuum

Question 3

What is a wavelengh (λ)

Answer 3

Distance between two
consecutive peaks or troughs in a wave

Question 4

What is frequency (v)

Answer 4

Number of waves (cycles) per
second that pass a given point in space

Question 5

What is the unit for the speed of light (c)

Answer 5

2.9979 × 10^8 m/s

Question 6

What is the realtionship between wavelength and frequency

Answer 6

an inverse relationship

Question 7

Short-wavelength radiation has a _____________
frequency when compared to long-wavelength radiation

Answer 7

higher

Question 8

What did Max Planck say

Answer 8

Postulated that energy can be gained or lost only in whole number multiples of h ν

Question 9

Formula for representing change in energy

Answer 9

ΔE = nhv
n - Integer
h - Planck’s constant
ν - Frequency of electromagnetic radiation absorbed oremitted

Question 10

What was the conclusion from Planck’s Postulate

Answer 10

Energy is quantized and can occur in discrete units of hν

Question 11

Formula to calculate quantum energy

Answer 11

ΔE = hv

Question 12

What did Albery Einstein propose

Answer 12

Proposed that electromagnetic radiation is a stream of particles called photons

Question 13

What is the photoelectric effect

Answer 13

Phenomenon in which electrons are emitted from the surface of a metal when light strikes it

Question 14

Regarding the photoelectric effect:

what happends when frequency of light is varied

Answer 14

When frequency of light is varied, no electrons are emitted by a given metal below the threshold
frequency (ν0)

Question 15

Regarding the photoelectric effect:

When ν < v0:

Answer 15

When ν < v0 , no electrons are emitted, regardless of the intensity of the light

Question 16

Regarding the photoelectric effect:

When v > v0:

Answer 16

• The number of electrons emitted increases with the intensity of the light
• The kinetic energy (KE) of the emitted electrons increases linearly with the frequency of the light

Question 17

What is the symbol representing the minimum energy required to remove an electron

Answer 17

E0 = hv0

Question 18

Formula by Einstein regarding energy and mass

Answer 18

E = mc^2

Question 19

What is the dual nature of light

Answer 19

Electromagnetic radiation exhibits wave and particulate properties

Question 20

What did Louis de Broglie claim

Answer 20

He postulated the wave nature of electrons and suggested that all matter has wave properties.

Question 21

What is a continuous spectrum

Answer 21

Results when white light is passed through a prism
- Contains all the wavelengths of visible light

Question 22

What is the line spectrum

Answer 22

The line spectrum shows only certain discrete wavelengths

Question 23

What is the quantum model

Answer 23

The electron in a hydrogen atom moves around the nucleus in certain allowed circular orbits
- Tendency of the revolving electrons to fly off the atom can be balanced by its attraction to the positively charged nucleus

Question 24

What is borh’s model

Answer 24

Expression for energy levels available to the electrons in the hydrogen atom

Question 25

What does the negative sign imply in Bohr's model

Answer 25

Negative sign implies that the energy of the electron bound to the nucleus** is lower than it would be **if the electron were at an infinite distance from the nucleus

Question 26

In the Bohr model, what is the ground state

Answer 26

Lowest possible energy state

Question 27

Is the energy of the electron in any orbit is positive or negative relative to the reference state (n = ∞)

Answer 27

It is negative

Question 28

Formula for the calculation of change in Energy (ΔE) and Wavelength of the Emitted Photon

Answer 28

Δ E = energy of final state - energy of initial state

Question 29

What does it mean if in ΔE =E2-E1, ΔE has a positive value

Answer 29

The positive value for ΔE indicates that the system has **gained energy**

Question 30

What happends as the electron becomes more tightly bound

Answer 30

As the electron becomes more tightly bound, its energy becomes **more negative** relative to the zero energy reference state

Question 31

As the electron is brought closer to the nucleus, is energy absorbed or released from the system

Answer 31

it is released

Question 32

How is the electron in a hydrogen atom imagined

Answer 32

it is imagined to be a standing wave

Question 33

7.5!!!

Question 34

What are quantum numbers

Answer 34

Series of numbers that express various properties of an orbital - Principal quantum number (n) - Angular momentum quantum number (l) - Magnetic quantum number (m1)

Question 35

For principal quantum numbers, what happends as the value of *n* increase | (3)

Answer 35

- The orbital becomes larger - The electron spends more time away from the nucleus - The energy increases since the electron is less tightly bound to the nucleus (Energy is less negative)

Question 36

What is the principal quantum number related to

Answer 36

Related to the size and energy of an orbital

Question 37

# What am I? Has integral values (1, 2, 3, …)

Answer 37

Principal Quantum Number

Question 38

# What am I? Has integral values from 0 to n 1 for each value of n

Answer 38

Angular Momentum Quantum Number

Question 39

# What am I? Has integral values between 1 and -1 (includes zero)

Answer 39

Magnetic Quantum Number

Question 40

What is the Angular Momentum Quantum Number related to

Answer 40

Related to the shape of atomic orbitals

Question 41

For the Angular Momentum Quantum Number, what letter is each value of l assigned to?

Answer 41

0 = s 1 = p 2 = d 3 = f 4 = g ## Footnote Each set of orbitals with a given value of l (subshell) is designated by giving the value of n and the letter for l

Question 42

What is the value of the Magnetic Quantum Number related to

Answer 42

Value is related to the orientation of an orbital in space relative to the other orbitals in the atom

Question 43

# Which orbital am I? Characterized by their spherical shape; shape becomes larger as the value of n increases

Answer 43

S orbitals

Question 44

2 s and 3 s orbitals have areas of ---------- probability separated by areas of ---------- probability

Answer 44

2 s and 3 s orbitals have areas of **high probability** separated by areas of** low probability**

Question 45

For s orbitals, how do you calculate the number of notes

Answer 45

Number of nodes is given by n-1

Question 46

# True or false s orbital function is always positive in two dimensional space

Answer 46

False. s orbital function is always positive in **three** dimensional space

Question 47

# Define: nodes

Answer 47

Areas of zero probability in an orbital

Question 48

What causes the number of notes to increase

Answer 48

Number of nodes increases as n increases

Question 49

Where do d orbitals first appear

Answer 49

In level n=3