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Which of the following statements are correct?

Hint given in feedback

Hint given in feedback

Select one or more:

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

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

E = hf

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

E = (6.63 * 10^-34 Js)( 6.24 x 10^{14} hertz) = 2.10E-19 J

Match properties correctly.

l=3 | |

Indicates energy and size of orbital | |

l=2 | |

Number of possible electron spins for each orbital | |

l=0 | |

l=1 |

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:

E = hf

E = hc/ λ

The smaller the wavelength the greater the energy

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 | |

Spherically symmetric orbital--no nodal planes | |

The maximum number of electrons in an electron orbital. | |

Orbital shaped like a peanut or dumbbell--one nodal plane | |

4 of the 5 orbitals shaped like a double peanut--2 nodal planes |

If n = 2, what are the allowed values of *l*?

Select one or more:

Match the number of orbitals for s, p, d, and f orbitals.

5d | |

5s | |

5f | |

5p |

Which of the following are allowed spins for an electron in an orbital?

Select one or more:

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

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:

Orbital lowest in energy | |

Orbital 2nd lowest in energy | |

Orbital 3rd lowest in energy | |

Orbital 4th lowest in energy | |

Orbital 5th lowest in energy | |

Orbital 6th lowest in energy | |

Orbital 7th lowest in energy |

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

What is the ground state electron configuration of B?

For F, 1s^{2}2s^{2}2p^{5}, write 1s22s22p5 or 1s2 2s2 2p5.

For F, 1s

What is the ground state electron configuration of Na?

What is the ground-state electron configuration for S?

Select one:

Select one:

with -2 charge (we add 2 electrons) :

Select one:

Orginal: 1s^{2}2s^{2}2p^{6}3s^{2}3p^{ 6 } 4s^{1} ^{}

^{}

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

1s^{2}2s^{2}2p^{6}3s^{2}3p^{ 6}^{}

What is the abbreviated or short-hand ground state electron configuration for Al? For Sc it is [Ar]4s^{2}3d^{1}, for Moodle write [Ar]4s23d1 or [Ar] 4s2 3d1.

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

So everything after it is: 3s23p1

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

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

So everything after it is: 4s23d104p5

Which of the following electron configurations is correct for the ground state of O?

Select one:

Which of the following electron configurations is correct for the ground state of P?

Select one:

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

There are 5 unpaired electrons in the d orbital

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

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)

*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

Hint given in feedback

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?

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

Hint given in feedback

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^{}