Chapter 2: Atomic Structure. Electron Configuration

Question 1

What does the relative atomic mass represent?

Answer 1

The average mass of an atom of the element.

Question 2

What is the maximum number of electrons a single orbital can hold?

Answer 2

2 electrons.

Question 3

What is the shape of an s orbital?

Answer 3

Spherical.

Question 4

How many orbitals are present in the p subshell?

Answer 4

3 orbitals.

Question 5

What is the maximum number of orbitals in a shell determined by?

Answer 5

n² (where n is the shell number).

Question 6

How many orbitals does the d subshell have?

Answer 6

5 orbitals.

Question 7

How many electrons can the p subshell hold?

Answer 7

6 electrons.

Question 8

What is Hund’s third rule?

Answer 8

Electrons occupy separate orbitals with parallel spins to minimize energy.

Question 9

What is the relationship between 4s and 3d orbitals?

Answer 9

They are close in energy.

Question 10

What is particularly stable in electron configurations?

Answer 10

Half-filled and fully filled sub-levels.

Question 11

How does electron configuration influence an element’s position on the Periodic Table?

Answer 11

It is based on the sub-level of highest energy in the ground-state atom.

Question 12

Why does successive ionization energy increase?

Answer 12

Greater attractive force between protons and remaining electrons.

Question 13

What are the three factors influencing ionization energy?

Answer 13

• Nuclear charge
• Distance between nucleus - outer electrons
• Shielding effects

Question 14

How does nuclear charge affect ionization energy?

Answer 14

Ionization energy increases with proton number.

Question 15

What is the effect of electron distance from the nucleus on ionization energy?

Answer 15

Farther distance lowers ionization energy.

Question 16

How does the shielding effect influence ionization energy?

Answer 16

More inner electron shells reduce ionization energy.

Question 17

How does electron configuration minimize electron repulsion?

Answer 17

Electrons occupy separate orbitals.

Question 18

What is the maximum number of electrons in an f subshell?

Answer 18

14 electrons.

Question 19

What determines the energy levels of orbitals?

Answer 19

The principal quantum number (n) and subshell type.

Question 20

Why are parallel spins favored in orbitals?

Answer 20

They lower energy by minimizing repulsion.

Question 21

What is the shape of p orbitals?

Answer 21

Dumbbell-shaped.

Question 22

How many p orbitals exist in a shell?

Answer 22

3 orbitals.

Question 23

What is the maximum number of electrons in the n=3 shell?

Answer 23

18 electrons.

Question 24

Which subshell has 7 orbitals?

Answer 24

f subshell.

Question 25

How does first ionization energy change across a period?

Answer 25

It generally increases.

Question 26

Why does ionization energy decrease down a group?

Answer 26

Increased shielding and electron distance.

Question 27

How many electrons can a d subshell hold?

Answer 27

10 electrons.

Question 28

What is the significance of a full d subshell?

Answer 28

Stability in the atom.

Question 29

Which orbitals are occupied first, 4s or 3d?

Answer 29

4s

Question 30

How are orbitals arranged within subshells?

Answer 30

They are filled to minimize energy.

Question 31

What is the maximum number of electrons in the n=2 shell?

Answer 31

8 electrons.

Question 32

What happens to electron repulsion in a full subshell?

Answer 32

It is minimized due to pairing.

Question 33

How many orbitals are there in an s subshell?

Answer 33

1 orbital.

Question 34

What subshells exist in the n=1 shell?

Answer 34

s subshell only.

Question 35

What is the principle behind the Aufbau process?

Answer 35

Electrons fill the lowest energy orbitals first.

Question 36

Which rule explains why no two electrons in an atom can have the same set of quantum numbers?

Answer 36

Pauli exclusion principle.

Question 37

What is the significance of orbital overlap in bonding?

Answer 37

It allows sharing of electrons.

Question 38

What factors determine the energy difference between orbitals?

Answer 38

Subshell type and nuclear charge.

Question 39

How does the shielding effect vary with atomic number?

Answer 39

It increases with more inner electron shells.

Question 40

How does the energy of 4p orbitals compare to 4s?

Answer 40

4p orbitals have higher energy.

Question 41

What is the shape of d orbitals?

Answer 41

Complex

Question 42

What rule governs the order of filling electron orbitals?

Answer 42

Aufbau principle.

Question 43

How many electrons can the 3p subshell hold?

Answer 43

6 electrons.

Question 44

What is the maximum number of orbitals in the n=4 shell?

Answer 44

16 orbitals.

Question 45

What explains the stability of noble gases?

Answer 45

Full outer electron shells.

Question 46

How does electron spin contribute to magnetic properties?

Answer 46

Unpaired spins create magnetic moments.

Question 47

What is the electron configuration of helium?

Answer 47

1s².

Question 48

How does the periodic table reflect electron configurations?

Answer 48

By grouping elements with similar outer electron configurations.

Question 49

Why does the first ionization energy of sodium drop compared to neon?

Answer 49

Sodium has an electron in a higher energy shell.

Question 50

What happens when an atom gains an electron?

Answer 50

It forms an anion.

Question 51

How does nuclear attraction affect ionization energy?

Answer 51

Greater attraction increases ionization energy.

Question 52

What is the electron configuration of carbon?

Answer 52

1s² 2s² 2p².

Question 53

How does ionization energy vary in a transition metal series?

Answer 53

It varies slightly due to d orbital filling.

Question 54

Which subshells are involved in the electron configuration of oxygen?

Answer 54

s and p subshells.

Question 55

What property of electrons leads to Hund’s rule?

Answer 55

Spin pairing energy.

Question 56

How do energy levels change as n increases?

Answer 56

They become closer together.

Question 57

What happens to atomic size as ionization energy increases?

Answer 57

It decreases.