Electron Configuration

Question 1

What is the principle quantum number?

Answer 1

the main energy level/shell
the further the shell is from the nucleus, the higher the number

Question 2

Do electrons have the same energy in each shell?

Answer 2

No, the have different energies

Question 3

What are the shells divided into(names)and what do they make up?

Answer 3

Subshells: s,p,d
the subshells make up the principle energy levels.

Question 4

How many electrons can each subshell hold + orbitals?

Answer 4

s = 2 electrons - 1 orbital
p = 6 electrons - 3 orbitals
d = 10 electrons - 5 orbitals

Question 5

What is an orbital?

Answer 5

Region of space around the nucleus of an atom where there is a high chance of finding the electron.

Question 6

How many electrons can 1 orbital hold?

Answer 6

2 electrons

Question 7

State the principle level, numberof sub shell and orbital

Answer 7

level 1 = 1 sub shell = s
level 2 = 2 sub shells = s,p
level 3 = 3 sub shells = s,p,d

Question 8

Write the sub shell notation for Potassium (19)

Answer 8

1s2 2s2 2p6 3s2 3p6 4s1

Question 9

When writing box notations, why must the arrows be facing in the opposite direction and what does the direction of the arrow represent?

Answer 9

To show electron replusion, the direction of the arrow represents the spin of the electron.

Question 10

What are the outliers for sub shell notation.

Answer 10

Copper (Cu) & Chromium (Cr)
They both donate one of their 4s electrons to the 3d subshells.
Cr = 3d5 4s1
Cu = 3d10 4s1
- having 3d5 and 3d10 is more stable.

Question 11

What is ionisation energy?

Answer 11

The minimum amount of energy required to remove one mole of electrons from 1 mole of gaseous atoms to form 1 mole of gaseous ions

Question 12

Write the first ionisation energy for X.

Answer 12

X(g) -> X+(g) + e-

Question 13

State and explain the factors affecting ionisation energy

Answer 13

1) Shielding
- As shielding increases, the electrostatic force between the nucleus and the electrons decreases which means the ionisation energy decreases, making it easier to lose an e-
2) Nuclear charge
- The higher the nucleus charge is in the nucleus, the higher the electrostatic force between the nucleus and the e- which means the ionisation energy increases making it harder to lose an e-
3) Distance from the nucleus
- The larger the distance is from the nucleus to the e- the weaker the electrostatic force is which means ionisation energy decreases making it easier to lose an e-

Question 14

What is the trend of ionisation energies down a group?

Answer 14

Shielding, nuclear charge and distance increase as you go down a group but shielding and distance increase significantly more than nuclear charge therefore ionisation energy decreases down a group.