2.2.1 Electron structure Flashcards
How many electrons can the first four shells hold?
1st shell = 2 electrons; 2nd shell = 8 electrons; 3rd shell = 18 electrons; 4th shell = 32 electrons.
Define an atomic orbital.
A region around the nucleus that can hold up to two electrons with opposite spins.
What is the shape of an s-orbital?
Spherical.
What is the shape of a p-orbital?
Dumbbell-shaped.
How many orbitals make up an s-sub-shell?
1 orbital.
How many orbitals make up a p-sub-shell?
3 orbitals.
How many orbitals make up a d-sub-shell?
5 orbitals.
How many electrons can fill an s-sub-shell?
2 electrons.
How many electrons can fill a p-sub-shell?
6 electrons.
How many electrons can fill a d-sub-shell?
10 electrons.
In what order do orbitals fill for the first three shells and the 4s and 4p orbitals?
1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p.
How do orbitals of the same energy fill according to the Pauli exclusion principle?
Orbitals of the same energy are occupied singly before pairing occurs.
What is the electron configuration for an atom with Z = 8 (oxygen)?
1s2 2s2 2p4.
What is the electron configuration for an atom with Z = 17 (chlorine)?
1s2 2s2 2p6 3s2 3p5.
What is the electron configuration for an atom with Z = 36 (krypton)?
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6.
What is the electron configuration for a Na+ ion (Z = 11)?
1s2 2s2 2p6.
What is the electron configuration for a Cl- ion (Z = 17)?
1s2 2s2 2p6 3s2 3p6.
What model should be used to represent electron configurations?
Electrons-in-box representations with opposite spins shown as arrows.
What notation should be used to show electron configurations in OCR A Level Chemistry?
Sub-shell notation, e.g., oxygen: 1s2 2s2 2p4.
State the number of electrons in the fourth shell of ytterbium.
32 ✓
How many orbitals are there in the third shell of ytterbium?
9 (3s, 3p, 3d)
Complete the electron configuration of a manganese atom.
1s 2s 2p6 3s2 3p6 3d5 4s2✓
State the 3D shape of an s-orbital and a p-orbital.
s-orbital: spherical ✓
p-orbital: dumb-bell shape ✓
