Chapter 5 - Electrons and bonding

Question 1

What is the principle quantum number, n?

Answer 1

The shell number/energy level

Question 2

What is an atomic orbital?

Answer 2

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

Question 3

What are the four different types of atomic orbital?

Answer 3

s, p, d, f

Question 4

What is the shape of an s orbital, and how many does each shell contain?

Answer 4

Shaped like a sphere, each shell from n = 1 contains one s orbital

Question 5

What is the shape of a p orbital and how many does each shell contain?

Answer 5

Shaped like a dumb bell, each shell from n = 2 contains three p orbitals

Question 6

How many d orbitals does each shell contain?

Answer 6

Each shell from n = 3 contains five d orbitals

Question 7

How many f orbitals does each shell contain?

Answer 7

Each shell from n = 4 contains seven f orbitals

Question 8

How do orbitals fill?

Answer 8

Orbitals fill in order of increasing energy

Question 9

How do electrons pair in an orbital?

Answer 9

One electron occupies each orbital before pairing starts, preventing any repulsion between paired electrons until there is no further orbital available at the same energy level

Question 10

Why does the 4s orbital fill before the 3d orbital?

Answer 10

Because 3d is at a higher energy level than the 4s sub shell, so the 4s sub shell will fill first

Question 11

What is ionic bonding?

Answer 11

The electrostatic attraction between positive and negative ions

Question 12

What structure do ionic compounds form?

Answer 12

Giant ionic lattice

Question 13

What is a giant ionic lattice?

Answer 13

A repeating pattern of oppositely charged ions

Question 14

Why do most ionic compounds have high melting and boiling points?

Answer 14

There are strong electrostatic forces of attraction between the oppositely charged ions in the giant ionic lattice, high temperatures are needed to provide the large amounts of energy needed to overcome this attraction

Question 15

Why do most ionic compounds dissolve in water?

Answer 15

The polar nature of solvents such as water break down the lattice, and attract and surround each ion in solution

Question 16

Why do ionic compounds only conduct electricity when molten or in solution?

Answer 16

In the solid state, the ions are in a fixed position and there is no way to carry charge. Whereas in a molten state, the ionic lattice is broken and the ions are free to move and carry charge

Question 17

What is covalent bonding?

Answer 17

The strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms

Question 18

What happens to atomic orbitals in covalent bonds?

Answer 18

They overlap, giving a pair of shared electrons

Question 19

What is a multiple covalent bond?

Answer 19

When two atoms share more than one pair of electrons

Question 20

What is a dative covalent bond?

Answer 20

A covalent bond in which the shared pair of electrons has been supplied by one of the bonding atoms only (was originally a lone pair)

Question 21

Why can the non-metals in Period 3 form different numbers of covalent bonds?

Answer 21

The n = 3 outer shell can hold 18 electrons so more electrons are available for bonding, and there are different electron pairing arrangements

Question 22

What is average bond enthalpy?

Answer 22

A measurement of covalent bond strength