Question

1. in the photoelectric effect, increasing the frequency of the light increases the ______ of the ejected electrons.

a. number
b. energy
c. size
d. wavelength

1. if a radio station were to increase its frequency from 94.5 mhz to 99.1 mhz, what would happen to the stations wavelength?

a. the wavelength would not change.
b. the wavelength would go up.
c. the wavelength would go down.
d. the wavelength would double.

1. the heisenberg uncertainty principle states that __________.

a. no two electrons in the same atom can have the same set of four quantum numbers
b. two atoms of the same element must have the same number of protons
c. it is impossible to simultaneously know the precise position and velocity of a particle
d. electrons of atoms in their ground states enter energetically equivalent sets of orbitals singly before they pair up in any orbital of the set.

1. the ground state of hydrogen corresponds to the ______.

a. zeroth energy level
b. first energy level
c. second energy level
d. highest energy level

1. which of the following statements is true?

a. each set of orbitals contains seven orbitals.
b. each set of orbitals can hold a maximum of 14 electrons.
c. the first energy level contains only s and p orbitals.
d. all s orbitals are spherically shaped.

1. what is the primary difference between the 1s and the 2s orbitals?

a. shape
b. size
c. number of electrons
d. number of neutrons

1. in the bohr model of the hydrogen atom, which of the following transitions results in light you can see?

a. n = 6 to n = 1
b. n = 6 to n = 2
c. n = 6 to n = 3
d. n = 6 to n = 4

1. the principle that states each electron occupies the lowest energy orbital available is the ______.

a. aufbau principle
b. uncertainty principle
c. exclusion principle
d. photoelectric principle

Explanation:

• Question 9: In the photoelectric effect, the energy of a photon is given by \(E = h

u\) (where \(h\) is Planck's constant and \(
u\) is the frequency). When the frequency of light increases, the energy of the photons increases. The number of electrons (a) is related to the intensity of light (number of photons), size (c) is not relevant in this context, and wavelength (\(d\), \(\lambda=\frac{c}{
u}\), \(c\) is the speed of light) is inversely related to frequency but not directly related to the energy of ejected electrons in the way the question asks.

• Question 10: The relationship between frequency (\(

u\)) and wavelength (\(\lambda\)) is \(c=
u\lambda\) (where \(c\) is the speed of light). If \(
u\) increases (\(c\) is constant), then \(\lambda=\frac{c}{
u}\) decreases.

• Question 11: The Heisenberg uncertainty principle states that it is impossible to simultaneously know the precise position and velocity (momentum, \(p = mv\)) of a particle. Option a is the Pauli - exclusion principle, option b is a property of elements (atomic number = number of protons), and option d is Hund's rule.
• Question 12: The ground state of an atom is the lowest energy state. For hydrogen, the first energy level (\(n = 1\)) is the ground state.
• Question 13: All s orbitals are spherically - shaped. Option a: For example, p - orbitals have 3 orbitals in a set, d - orbitals have 5. Option b: Each orbital can hold 2 electrons, so a set of orbitals (e.g., p - set with 3 orbitals can hold 6 electrons). Option c: The first energy level (\(n = 1\)) has only s orbitals.
• Question 14: 1s and 2s orbitals have the same shape (spherical), but 2s is larger in size. The number of electrons in an orbital can vary (but is not the primary difference here), and neutrons are not related to orbitals.
• Question 15: Transitions to \(n = 2\) (Balmer series) result in visible light. Transitions to \(n=1\) (Lyman series) are in the ultraviolet, and transitions to \(n = 3\) and \(n = 4\) (Paschen and Brackett series) are in the infrared.
• Question 16: The Aufbau principle states that each electron occupies the lowest energy orbital available. The uncertainty principle (b) is about position and momentum, the exclusion principle (c) is about quantum numbers, and the photoelectric principle (d) is about electron ejection from a metal surface.

Answer:

1. b. energy
2. c. The wavelength would go down.
3. c. it is impossible to simultaneously know the precise position and velocity of a particle
4. b. first energy level
5. d. All s orbitals are spherically shaped.
6. b. size
7. b. \(n = 6\) to \(n = 2\)
8. a. Aufbau principle