Quantum Numbers and Electron Distribution

What quantum number describes the energy of an orbital?

• angular (ℓ)
• magnetic (mℓ)
• principal (n)
• spin (ms)

Which of the following best describes a paramagnetic atom?

• An atom where all the electrons are paired.
• An atom where some of the electrons are unpaired.
• Atoms that are not attracted to a magnetic field.
• None

The spin quantum number is defined by which of the following?

• The orientation or shape of the orbital the electron is in.
• The orientation of orbitals around the nucleus.
• The energy level the electron is in.
• The direction of electron spin.

The angular quantum number is defined by which of the following?

• The shape of the orbital the electron is in.

• The orientation of orbitals around the nucleus.
• The energy level the electron is in.

• The direction of electron spin.

How many orientations can the s orbital have?

• 1

• 3

• 5

• 7

An orbital in the second energy level (n = 2) can hold up to how many electrons?

• 2

• 18

• 8

• 32

The word aufbau came from the German word aufbeen, which means "build up." Which of the following describes the Aufbau Principle?

• electrons with the same spin cannot occupy the same orbital.

• since electrons repel each other, electrons will occupy single orbitals within an energy level before doubling up

• electrons fill lower energy levels first before occupying higher energy levels.

• electrons must have oppposite spins

If the principal quantum number n is 4, what are the possible values for the azimuthal quantum number l?

• • l = 0, 1, 2, 3

• • l = 0, 1, 2

• • l = 0, 1, 2, 3, 4

• • l = 3

What is the principal quantum number for an electron in the 5s orbital?

• 5

• 4

• 3

• 1

Which among the following quantum numbers is invalid?

• n=3

• l=2

• ml=3

• ms= +1/2