What is the principal quantum number (n) for an electron in the 3s subshell? Solution: The principal quantum number for the 3s subshell is 3.

- How many orbitals are present in a 4f subshell? Solution: The 4f subshell has 7 orbitals.
- What are the possible values of the magnetic quantum number (ml) for an electron in a 4f orbital? Solution: The possible values of ml for a 4f orbital are -3, -2, -1, 0, 1, 2, 3.
- Which quantum number indicates the shape of an orbital? Solution: The azimuthal quantum number (l) indicates the shape of an orbital.
- What is the azimuthal quantum number (l) for an electron in the 2p subshell? Solution: The azimuthal quantum number for a 2p subshell is 1.
- How many total orbitals are there in the third energy level (n=3)? Solution: The total number of orbitals in the third energy level is given by n², so there are 3² = 9 orbitals.
- What does the spin quantum number (ms) of -½ signify? Solution: The spin quantum number of -½ signifies that the electron is spinning in the opposite direction to the one spinning with a +½ spin quantum number.
- How many electrons can occupy the 3d subshell? Solution: The 3d subshell can hold a maximum of 2×5 = 10 electrons.
- What is the magnetic quantum number (ml) for an electron in the s orbital? Solution: The magnetic quantum number for an electron in the s orbital is 0.
- How many electrons are in the 2s subshell of a lithium (Li) atom? Solution: The electron configuration of lithium is 1s² 2s¹, so there is 1 electron in the 2s subshell.
- Which quantum number is associated with the orientation of an orbital in space? Solution: The magnetic quantum number (ml) is associated with the orientation of an orbital in space.
- How many orbitals are there in a p subshell? Solution: A p subshell has 3 orbitals.
- How many total electrons can be found in the second energy level (n=2)? Solution: The total number of electrons that can be found in the second energy level is given by 2n², so there are 2×2² = 8 electrons.
- What is the spin quantum number (ms) for an electron in a magnesium (Mg) atom? Solution: The spin quantum number for any electron can only be either +½ or -½.
- How many electrons are in the 2p subshell of a nitrogen (N) atom? Solution: The electron configuration of nitrogen is 1s² 2s² 2p³, so there are 3 electrons in the 2p subshell.
- What is the principal quantum number (n) for an electron in the outermost shell of an oxygen (O) atom? Solution: Oxygen is in the 2nd period of the periodic table, so the principal quantum number for its outermost shell is 2.
- Which quantum number determines the energy of an electron in a hydrogen atom? Solution: The principal quantum number (n) determines the energy of an electron in a hydrogen atom.
- How many electrons can be held in the n=4 energy level? Solution: The n=4 energy level can hold a maximum of 2n² = 2×4² = 32 electrons.
- What are the four quantum numbers (n, l, ml, ms) for the last electron added to a phosphorus (P) atom? Solution: The electron configuration of phosphorus is [Ne] 3s² 3p³. The four quantum numbers for the last electron added are n=3, l=1, ml=1, ms=+½.
What does the azimuthal quantum number (l) of 3 represent? Solution: The azimuthal quantum number of 3 represents an f subshell.