Electron Configuration

Question 1

What are main energy levels/ shells split into?

Answer 1

• Sub-shells (orbitals.)

Question 2

What are the 4 types of orbitals?

Answer 2

• s,p,d,f.

Question 3

How many sub-orbitals does an s orbital contain?

Answer 3

• One sub- orbital.
  MAXIMUM NUMBER OF ELECTRONS IN SUB SHELL = 2

Question 4

How many electrons does 1 sub- orbital hold?

Answer 4

• 2 electrons.

Question 5

How many sub -orbitals does a p orbital cotain?

Answer 5

• Three sub- orbitals
  MAXIMUM NUMBER OF ELECTRONS IN SUB-SHELL = 6

Question 6

How many sub- orbitals does a d orbital contain?

Answer 6

• Five sub- orbitals
  MAXIMUM NUMBER OF ELECTRONS IN SUB-SHELL = 10

Question 7

What sub-shell does the first energy level have?

Answer 7

• An s sub-shell.(orbital)

Question 8

What sub-shells does the second energy level have?

Answer 8

• An s sub-shell. (orbital)
• A p sub shell. (orbital)

Question 9

What sub-shells does the third energy level have?

Answer 9

• An s sub-shell (orbital)
• A p sub-shell (orbital)
• A d sub-shell (orbital.)

Question 10

What sub-shells does the fourth energy level have?

Answer 10

• An s sub shell (orbital)
• A p sub shell (orbital)
• A d sub shell (orbital)
• (A f sub-shell.)

Question 11

What order are the sub-shells filled with electrons in?

(Draw out diagram/ do cross down technique.)

Answer 11

1s, 2s, 2p,3s,3p,4s,3d,4p,5s, 4d, 5p, 6s

Question 12

Finish sentence

Groups 1 and 2 are ….. ……. elements.

Answer 12

s block

Question 13

FIllin gaps

Groups 3 to 12 are ….. ……. elements.

Answer 13

d block

Question 14

Fill the gaps

Groups 3 to 0 are ….. ….. elements

Answer 14

p block.

Question 15

Explain what each aspect of this configuration: (1s¹) means

Answer 15

• 1 = first MAIN ENERGY LEVEL.
• s: type of orbital.
• 1 = number of electrons in the orbital.

Question 16

What is an orbital?

Answer 16

• Orbital: a region of space where there is a high probability of finding an electron.

Question 17

What equation will allow you to calculate the total number of electrons found in n main energy level?

Answer 17

2n²

Question 18

What shape does the s sub-shell have?

Answer 18

• A spherical shape.

Question 19

What is the shape of the p orbital?

Answer 19

• Each sub-orbital in p orbital in shape of dumbell.
• All together = shape of flower

Refer to Gautum notes if needed.

Question 20

Give two reasons why the 1s orbital is the most stable.

Answer 20

• Closest orbital to nucleus.
• Posesses least amount of energy.

Question 21

Finish the sentence

As the energy of the orbitals increase, the stability of the orbitals …….

Answer 21

• Decreases.

Question 22

How many sub-orbitals is f orbital made up of?

Answer 22

• 7 sub -orbitals
  MAXIMUM OF 14 ELECTRONS OVERALL

Question 23

What are the two elements that are the exceptions to filling orbitals in order and then moving onto the next (ie. they have a half-filled orbital?)

Answer 23

• Chromium
• Copper.

Question 24

What would you EXPECT the electron configuration of chromium to be?
What actually is the configuration?

Answer 24

• EXPECT: 1s²2s²2p⁶3s²3p⁶4s²3d⁴
• ACTUAL:
• 1s²2s²2p⁶3s²3p⁶4s¹3d⁵
  (Only PARTIALLY FILLED s orbital.)

Question 25

What would you expect the electron configuration of copper to be? What actually is the configuration?

Answer 25

EXPECT: - 1s²2s²2p⁶3s²3p⁶4s²3d⁹ ACTUAL: - 1s²2s²2p⁶3s²3p⁶3d¹⁰4s¹

Question 26

Why is the s orbital only partially filled in chromium and copper (ie. only one electron filled in s orbital and the electrons start filling in d orbital straight awa?)

Answer 26

- The arrangements are of lower energy so are more stable.

Question 27

What property do electrons have (beginning with s?)

Answer 27

- Spin.

Question 28

What is the spin of two electrons in the same orbital like?

Answer 28

- They have opposite spins. -

Question 29

What are electrons represented by in the spin diagrams? What does the direction of the arrows show?

Answer 29

- Electrons are represented by arrows. - Direction of the arrows show the different directions of spin.

Question 30

When doing box diagrams (ie. bus seating) how are the electrons filled in the sub-orbitals?

Answer 30

- You fill each sub-orbital individually before you start to pair the electrons up. - Ie. if you had a p orbital --> 3 sub-orbitals and there were 3 electrons, the 3 electrons would go in the 3 separate sub orbitals (no two electrons would be paired together.)

Question 31

Why do electrons fill individually in sub-orbitals before being paired up?

Answer 31

- Because if two electrons are in the same sub-orbital they will repel each other even more (requires even more energy to put the electrons in the same sub-orbital.)

Question 32

What does the opposite direction of spin of electrons in each sub-orbital reduce?

Answer 32

- The opposite direction of each of electrons in each sub-orbital reduces the mutal repulsion between the paired electrons.

Question 33

What is the short-hand way of writing the electron configuration of Titanium (22 electrons?) How do you do the short-hand electron configuration?

Answer 33

- (Ar) 4s²3d² - Locate noble gas above the element. - Go horizontally across until you reach your element (as you enter s block fill the s orbital and move onto the d block - fill the d orbital until you reach titanium: in this example.)

Question 34

Short-hand configuration of chromium.

Answer 34

(Ar) 4s¹ 3d⁵

Question 35

Where are electrons removed from when we ionise transition metals?

Answer 35

- Electrons are lost from the 4s orbital FIRST and then from the 3d, 3p, 3s etc (going down.)

Question 36

What is the short- hand electronic structure of Chromium? What does spin diagram look like?

Answer 36

(Ar)4s¹3d⁵ All filled up to 3p. 4s only partially filled, one extra in 3d. *the s orbital is partially-filled even in the short-hand configuration*

Question 37

# KLP Short-hand notation of V³⁺

Answer 37

(Ar) 3d² *NORMAL SHORT- HAND STRUCTURE? - (Ar)4s² 3d³.* - Take away 3 electrons - take two from 4s FIRST and then from the 3d!!

Question 38

# KLP If you want to write the electron configuration of a transition ion, what should you do? | 3 STEPS!!

Answer 38

1.) Write electron configuration of the atom. 2.) Then, take out electrons from the 4s first AND then the 3d. 3. ) There, you will have the full electron configuration of the ion.

Question 39

In general, how do we fill electrons in spin diagrams? Why do we do this?

Answer 39

- Put each electron in separate sub-orbital before starting to pair them up. - This requires less energy to do than if you started pairing electrons up to start off with (repulison force.)

Question 40

# Past Paper Q Which block contains the element Samarium (Sm?)

Answer 40

- f block

Question 41

What are: 2p, 2s, 3s, 4s.... etc. known as?

Answer 41

- Sub-orbitals.