Electron structure

Question 1

What does the principle quantum number indicate?

Answer 1

The shell occupied by the electrons

Question 2

What is a shell?

Answer 2

A group of orbitals with the same quantum number

Question 3

How many electrons can the first shell hold?

Answer 3

2

Question 4

How many electrons can the 2nd shell hold?

Answer 4

8

Question 5

How many electrons can the 3rd shell hold?

Answer 5

18

Question 6

How many electrons can the 4 th shell hold?

Answer 6

32

Question 7

What is an orbital?

Answer 7

A region around the nucleus that can hold up to two electrons with opposite spins.

Question 8

How many electrons can an orbital hold?

Answer 8

2

Question 9

What are the 4 types of orbitals?

Answer 9

S
P
D
F

Question 10

What is the shape of an s- orbital

Answer 10

Spherical

Question 11

What is the shape of a p-orbital?

Answer 11

Dumb bell shape

Question 12

How many orbitals are found in an s sub shell

Answer 12

1

Question 13

How many electrons can be held in a S sub shell

Answer 13

2

Question 14

How many orbitals does P sub shell have?

Answer 14

3

Question 15

How many be held in a P sub shell

Answer 15

6

Question 16

How many orbitals are present in a D sub shell

Answer 16

5

Question 17

How many electrons can be held in a D sub shell

Answer 17

10

Question 18

How many orbitals are found in an f sub shell

Answer 18

7

Question 19

How many electrons can fill F sub shell?

Answer 19

14

Question 20

When using electrons in a box what shape is used to represent the atom with an atomic number of 7 so electrons?

Answer 20

The first 2 electrons pair up on 1 s orbital
The second 2 electrons pair up in 2s orbital
They pair up with opposite spin.
The last 3 electrons singly occupy the 3 2p orbitals. They all have the same spin.

Question 21

What letter is used to represent the shell number?

Answer 21

n

Question 22

From which shell onwards is s orbital present?

Answer 22

n=1

Question 23

From which shell onwards is P-orbital present?

Answer 23

n=2

Question 24

From which shell onwards is d-orbital present?

Answer 24

n=3

Question 25

From which shell onwards is F- orbital present?

Answer 25

n=4

Question 26

What are the rules by which electrons are arranged in the shell?

Answer 26

Electrons are added one at a time
Lowest available energy level is filled first
Each energy level must be filled before the next one can fill
Each orbital is filled singly before pairing
4s is filled before 3d

Question 27

Why does 4s orbital fill before 3d orbital?

Answer 27

4s orbital has a lower energy than 3d before it is filled.

Question 28

What is the electron configuration of krypton?

Answer 28

1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^2 4p^6.

Question 29

What 2 elements are the exception to the electron configuration rule?

Answer 29

Chromium and copper
* a completely full or half full d sub-level is more stable than a partially filled d sub-level, so an electron from the 4s orbital is excited and rises to a 3d orbital.*

Question 30

What is the electronic configuration of copper?

Answer 30

1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^1

Question 31

What is the electronic configuration of chromium?

Answer 31

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

Question 32

Which electrons are last when an atom becomes a cation?

Answer 32

Electrons in the highest energy levels