F1 Atomic structures and properties

Question 1

three atom models:

Answer 1

Rutherford, Bohr, Quantum mechanical (Schrödinger)

Question 2

atomic orbitals

Answer 2

An atomic orbital is the region of space (defined by a wave function) where it is most likely to find an electron. An atomic orbital is characterized by the three quantum numbers n, l and ml.

Question 3

quantum numbers

Answer 3

n = principal quantum number
n = 1, 2, 3 … infinity, although 1 - 7 most important
tells you about the energy of the orbital

l = secondary quantum number
l = 0, 1, 2 … (n - 1), although 0 - 3 most important
tells you about the shape of the orbital
l=0 -> s
l=1 -> p
l=2 -> d
l=3 -> f

m l = magnetic quantum number
m l = - l to + l
tells you about the orientation of the orbital

Question 4

Aufbau principle

Answer 4

Aufbau principle: Electrons fill the orbitals of lowest energy first

Question 5

Pauli exclusion principle

Answer 5

Pauli exclusion principle: Two electrons in an atom cannot have the same four quantum numbers => The spin of two electrons in the same orbital must be opposite

Question 6

Hund’s rule

Answer 6

Hund’s rule: The orbitals of subshells (degenerate orbitals) are each filled singly with electrons of parallel spins

Question 7

radial and angular wavefunctions

Answer 7

Radial wavefunction, R(r), contains information about what happens to the wavefunction as the distance from the nucleus increases.

Angular wavefunction, Y(ϕ, θ), contains information about the shape of the orbital.

Question 8

spin

Answer 8

A fourth quantum number, m s, relates to the spin of the electron.

m s = +1/2 -> clockwise rotation around the axis of the electron (represented by ↑)

m s = -1/2 -> anti-clockwise rotation around the axis of the electron (represented by ↓)

Question 9

Rita och beskriv med ord väteatomen enligt:
a) Rutherford
b) Bohr

Answer 9

a) Rutherfords atommodell: Central plusladdad kärna och ett hölje av kringvandrande elektroner. Atomkärnan utgör en väldigt liten del av atomens volym (large volume of empty space).

b) Bohrs atommodell: En utveckling av Rutherfords modell med skillnaden att elektronerna rör sig runt kärnan i olika orbitaler med bestämda energinivåer.

Question 10

Enligt den kvantmekaniska modellen finns ”s” och ”p” orbitaler, rita strukturen av 2s och de tre 2p orbitaler.

Answer 10

-

Question 11

Hur många elektroner kan man placera i 2s orbitalen i de tre 2p orbitalerna och varför?

Answer 11

2 elektroner i 2s orbitalen, och 6 elektroner i 2p orbitalerna tillsammans

Question 12

Hur många d-orbitaler finns det i nivån n=3?

Answer 12

5 st

Question 13

Vad är elektronkonfigurationen för ämnet Ar?

Answer 13

1s^2 2s^2 2p^6 3s^2 3p^6