Atoms

Question 1

Principles of electrons

Heisenberg uncertainty principle

Answer 1

The position and momentum of an electron cannot be known simultaneously.

Question 2

Principles of electrons

Pauli exclusion principle

Answer 2

No two electrons can have the same four quantum numbers. Therefore: paired electrons must have opposite spin (one +1/2, other -1/2)

Question 3

Principles of electrons

Hund’s rule

Answer 3

All orbitals in a subshell must contain at least one electron before any orbital can be filled with a second electron.
The first electron in each orbital all have the same parallel spin, while the second electron in the orbital has opposite spin

Question 4

Principles of electrons

Aufbau principle

Answer 4

Electrons will fill the lower energy orbitals before moving to the higher energy orbitals.
Order in which energy of orbitals increases is determined by the (n+l) rule, where the sum of the principal (n) and azimuthal (l) quantum numbers determine the energy level of the orbital

Question 5

Principles of electrons

Diamagnetic vs paramagnetic

Answer 5

Diamagnetic: If there are no unpaired electrons. Results in being repelled by a magnetic field.

Paramagnetic: If there are any unpaired electrons. Results in being attracted by a magnetic field.

Question 6

Quantum numbers

Answer 6

Each orbital holds a maximum of 2 electrons

There are n2 orbitals per shell and therefore 2n2 electrons per shell
Each subshell holds 4l + 2 electrons.

For example the p subshell holds 6 electrons, the d subshell holds 10

Question 7

Quantum numbers

n

Answer 7

Question 8

Quantum numbers

l

Answer 8

Question 9

Quantum numbers

ml

Answer 9

Question 10

Quantum numbers

ms

Answer 10

Question 11

Constants and equations

Avogadro’s number

Answer 11

Question 12

Constants and equations

Speed of light in a vacuum

Answer 12

Question 13

Constants and equations

Planck’s constant (h)

Answer 13

Question 14

Constants and equations

Energy of a photon

Answer 14