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Question 1

Which of the following statements are correct?
Hint given in feedback
Select one or more:  Explanation

Under certain circumstance particle behave like waves and waves behave as particles.

Question 2

What is the energy in J of 1 photon whose frequency is 3.17 x 1014 hertz (cycles per second)? Use scientific notation. Explanation

E = hf
h = Planck's constant = 6.63 * 10^-34 Js

E = (6.63 * 10^-34 Js)( 6.24 x 1014 hertz) = 2.10E-19 J

Question 3

What is the frequency in Hz (hertz) of visible light whose wavelength is 637 nm? a nm = 10-9m. Use scientific notation.

Help: frequency Explanation

f = c /  λ

c= 3E8 m/s

f = (3E8 m/s)/  (637E-9 m) = 4.71E14

Question 4

Match properties correctly.

 l=3 Answer 1Choose...nfpds2 Indicates energy and size of orbital Answer 2Choose...nfpds2 l=2 Answer 3Choose...nfpds2 Number of possible electron spins for each orbital Answer 4Choose...nfpds2 l=0 Answer 5Choose...nfpds2 l=1 Answer 6Choose...nfpds2 Explanation Question 5

Exciting an electron to an orbital with higher principle quantum takes energy. Which of the following excitation requires the most energy for the H atom?

Select one: Explanation E = hf

E = hc/ λ

The smaller the wavelength the greater the energy

Question 6

Correctly match the information for the angular momentum quantum number (l) which gives the shape of the orbital.

 Orbital shaped like flower or fancy--3 nodal planes Answer 1Choose...2fspd Spherically symmetric orbital--no nodal planes Answer 2Choose...2fspd The maximum number of electrons in an electron orbital. Answer 3Choose...2fspd Orbital shaped like a peanut or dumbbell--one nodal plane Answer 4Choose...2fspd 4 of the 5 orbitals shaped like a double peanut--2 nodal planes Answer 5Choose...2fspd Explanation Question 7

If n = 3, what are the allowed values of l?
Select one or more:   Explanation Question 8

If n = 2, what are the allowed values of l?
Select one or more:  Explanation Question 9

Match the number of orbitals for s, p, d, and f orbitals.
 5d Answer 1Choose...3 orbitals7 orbitals1 orbital5 orbitals 5s Answer 2Choose...3 orbitals7 orbitals1 orbital5 orbitals 5f Answer 3Choose...3 orbitals7 orbitals1 orbital5 orbitals 5p Answer 4Choose...3 orbitals7 orbitals1 orbital5 orbitals Explanation Question 10

Which of the following are allowed spins for an electron in an orbital?
Select one or more:  Explanation

Electrons can spin only in positive and negative 1/2 directions

Question 11

Select the correct set of quantum mechanical numbers for an electron in an s, p, d, and f orbital. (4 correct answers.)

Select one or more:    Explanation Question 12

Match the electron orbital with its energy.

 Orbital lowest in energy Answer 1Choose...1s (1 orbital; max of 2 electrons)3p (3 orbitals; max of 6 electrons)2p (3 orbitals; max of 6 electrons)4s (1 orbital; max of 2 electrons)2s (1 orbital; max of 2 electrons)3s (1 orbital; max of 2 electrons)3d (5 orbital; max of 10 electrons) Orbital 2nd lowest in energy Answer 2Choose...1s (1 orbital; max of 2 electrons)3p (3 orbitals; max of 6 electrons)2p (3 orbitals; max of 6 electrons)4s (1 orbital; max of 2 electrons)2s (1 orbital; max of 2 electrons)3s (1 orbital; max of 2 electrons)3d (5 orbital; max of 10 electrons) Orbital 3rd lowest in energy Answer 3Choose...1s (1 orbital; max of 2 electrons)3p (3 orbitals; max of 6 electrons)2p (3 orbitals; max of 6 electrons)4s (1 orbital; max of 2 electrons)2s (1 orbital; max of 2 electrons)3s (1 orbital; max of 2 electrons)3d (5 orbital; max of 10 electrons) Orbital 4th lowest in energy Answer 4Choose...1s (1 orbital; max of 2 electrons)3p (3 orbitals; max of 6 electrons)2p (3 orbitals; max of 6 electrons)4s (1 orbital; max of 2 electrons)2s (1 orbital; max of 2 electrons)3s (1 orbital; max of 2 electrons)3d (5 orbital; max of 10 electrons) Orbital 5th lowest in energy Answer 5Choose...1s (1 orbital; max of 2 electrons)3p (3 orbitals; max of 6 electrons)2p (3 orbitals; max of 6 electrons)4s (1 orbital; max of 2 electrons)2s (1 orbital; max of 2 electrons)3s (1 orbital; max of 2 electrons)3d (5 orbital; max of 10 electrons) Orbital 6th lowest in energy Answer 6Choose...1s (1 orbital; max of 2 electrons)3p (3 orbitals; max of 6 electrons)2p (3 orbitals; max of 6 electrons)4s (1 orbital; max of 2 electrons)2s (1 orbital; max of 2 electrons)3s (1 orbital; max of 2 electrons)3d (5 orbital; max of 10 electrons) Orbital 7th lowest in energy Answer 7Choose...1s (1 orbital; max of 2 electrons)3p (3 orbitals; max of 6 electrons)2p (3 orbitals; max of 6 electrons)4s (1 orbital; max of 2 electrons)2s (1 orbital; max of 2 electrons)3s (1 orbital; max of 2 electrons)3d (5 orbital; max of 10 electrons) Question 13

For a ground state electron configuration, what is the next electron orbital to fill after the following orbitals have electrons in them?

1s 2s 2p 3s 3p 4s

Explanation Question 14

What is the ground state electron configuration of B?
For F, 1s22s22p5, write 1s22s22p5 or 1s2 2s2 2p5.

Explanation Question 15

What is the ground state electron configuration of Na?

Explanation  Question 16

What is the ground-state electron configuration for S?

Select one: Explanation Question 17

What is the ground state electron configuration for S2-?
Select one: Explanation

with -2 charge (we add 2 electrons) :

Question 18

What is the ground state electron configuration for K1+?
Select one: Explanation

Orginal: 1s22s22p63s23p 6 4s1

With +1 charge (we remove electron from highest energy level)

1s22s22p63s23p 6

Question 19

What is the abbreviated or short-hand ground state electron configuration for Al? For Sc it is [Ar]4s23d1, for Moodle write [Ar]4s23d1 or [Ar] 4s2 3d1.

Explanation

[Ne] includes the electron configuration up to the noble gas Ne.

So everything after it is: 3s23p1

Question 20

What is the abbreviated or short-hand ground state electron configuration for Br?

Explanation

[Ar] includes the electron configuration up to the noble gas Ar.

So everything after it is: 4s23d104p5

Question 21

Which of the following electron configurations is correct for the ground state of O?
Select one: Explanation Question 22

Which of the following electron configurations is correct for the ground state of P?
Select one: Explanation Question 23

How many unpaired electrons are in the ground state electron configuration for Mn?

Explanation There are 5 unpaired electrons in the d orbital

Question 24

How many unpaired electrons are in the ground state electron configuration for Fe?

Explanation There are 4 unpaired electrons in the d orbital

Question 25

Gamma rays are electromagnetic radiation of very short wavelength emitted by the nuclei of radioactive elements. A certain radioactive element emits a gamma ray with a frequency of 1.39 x 10 20  Hz.  Express the wavelength of this radiation in picometers. (1Hz = 1 s-1 and 1 picometer = 1E-12 m) Explanation

λ= c / f

c= 3E8 m/s

λ(3E8 m/s)/  (1.39 E 20) = 2.16 E-12 = 2.16 pm

Question 26

The photoelectric effect for a certain alloy has a threshold frequency of  9.20 x 10 14 Hz. For light of this frequency, find the energy of one mole of photons (in kJ).

Hint given in feedback Explanation

E = h f  x  ( # photons) / 1000

E = (6.63E-34)(9.20E14)(6.02E23) / 1000 = 367

Question 27

Electrons are ejected from sodium metal by any light that has a wavelength shorter than 544 nm. What is the kinetic energy of an electron (in J) that is ejected from sodium by light with a wavelength of 213 nm? Explanation

E = (hc/ λ) - (hc/λ)

E = [ (3E8 x 6.63E-34)/ (544 E-9) ] - [ (3E8 x 6.63E-34)/ (213 E-9) ]

E = 5.68E-19

Question 28

The charge of an electron is -1.602 x 10 -19 C. For the photoelectric effect, how many microamperes (1 A = 1 C/s) of electrical current are produced when a metal is bombarded by 5.30x10 13 photons each second? Assume that each photon has sufficient energy to eject one electron. (Note currents are reported as positive values.)

Hint given in feedback Explanation

E = (photon charge) x (number of photons) / (1E-6)

E =  (1.602 x 10 -19 C ) x ( 5.30x10 13) / (1E -6) = 8.49 mA