COVALENT Bonding

Question 1

When atoms _____ pairs of _______, they form _______ bonds.

Answer 1

When atoms share pairs of electrons, they form covalent bonds.

Question 2

Covalently bonded substances may consist of _________

Answer 2

Covalently bonded substances may consist of small molecules.

Question 3

Some covalently bonded substances have very _________molecules such as: _________

Answer 3

Some covalently bonded substances have very large molecules,such as polymers.

Question 4

Some covalently bonded substances have _______covalent
structures, such as __________and _____________

Answer 4

Some covalently bonded substances have giant covalent
structures, such as diamond and silicon dioxide

Question 5

Covalent bonds are formed between what type of atom

Answer 5

Covalent bonds are formed between non-metals

Question 6

Covalent bonds invlolve _______ electrons

Answer 6

Covalent bonds involve sharing electrons

Question 7

Name type of structures where their atoms are covalently bonded

Answer 7

Structures where their atoms are covalently bonded include:

Simple covalent molecules
Giant covalent structures

Question 8

Define covalent bond

Answer 8

The attraction between two atoms that share one or more pairs of electrons

Question 9

Give examples of simple covalent molecules

Answer 9

hydrogen,
chlorine,
oxygen,
nitrogen,
hydrogen chloride,
water,
ammonia
methane

Question 10

What happens when a covalent molecules melts

Answer 10

When a covalent molecules melts, it is the intermolecular forces that break

Question 11

What holds the atoms of simple covalent molecules and giant covalent structures together

Answer 11

Strong covalent bonds hold the atoms of the simple covalent molecules and giant covalent structures together.

Question 12

What happens when simple covalent molecules change state

Answer 12

When simple covalent molecules change state, it is the weak intermolecular forces that break

Question 13

In terms of the intermolecular forces, describe the structure of a gas of a simple covalent molecule

Answer 13

In a gas, the weak intermolecular forces have completely broken

Question 14

Draw the dot and cross diagram and stick diagram for hydrogen and state the formula

Answer 14

file:///C:/Users/44748/Documents/dot%20and%20cross,%20stick%20diagram%20diagrams%20of%20simple%20covalent%20molecules.pdf

Question 15

Draw the dot and cross diagram and stick diagram for ammonia and state the formula

Answer 15

file:///C:/Users/44748/Documents/dot%20and%20cross,%20stick%20diagram%20diagrams%20of%20simple%20covalent%20molecules.pdf

Question 16

Draw the dot and cross diagram and stick diagram for water and state the formula

Answer 16

file:///C:/Users/44748/Documents/dot%20and%20cross,%20stick%20diagram%20diagrams%20of%20simple%20covalent%20molecules.pdf

Question 17

Draw the dot and cross diagram and stick diagram for chlorine and state the formula

Answer 17

file:///C:/Users/44748/Documents/dot%20and%20cross,%20stick%20diagram%20diagrams%20of%20simple%20covalent%20molecules.pdf

Question 18

Draw the dot and cross diagram and stick diagram for oxygen and state the formula

Answer 18

file:///C:/Users/44748/Documents/dot%20and%20cross,%20stick%20diagram%20diagrams%20of%20simple%20covalent%20molecules.pdf

Question 19

Draw the dot and cross diagram and stick diagram for hydrogen chloride and state the formula

Answer 19

file:///C:/Users/44748/Documents/dot%20and%20cross,%20stick%20diagram%20diagrams%20of%20simple%20covalent%20molecules.pdf

Question 20

Draw the dot and cross diagram and stick diagram for carbon dioxide and state the formula

Answer 20

file:///C:/Users/44748/Documents/dot%20and%20cross,%20stick%20diagram%20diagrams%20of%20simple%20covalent%20molecules.pdf

Question 21

Draw the dot and cross diagram and stick diagram for methane and state the formula

Answer 21

file:///C:/Users/44748/Documents/dot%20and%20cross,%20stick%20diagram%20diagrams%20of%20simple%20covalent%20molecules.pdf

Question 22

In what state are small covalent molecules, usually, at room temperature and why?

Answer 22

Small covalent molecules are usually gases or liquids at room temperature (due to low mp and bp due to weak intermolecular forces)

Question 23

State the properties of Small covalent molecules

Answer 23

Small covalent molecules low melting points and boiling points.

Small covalent molecules do not conduct electricity

Small covalent molecules are usually liquids or gases at room temperature

Question 24

Explain why simple covalent molecules do not conduct electricity

Answer 24

Simple covalent molecules do not conduct electricity. This is because the molecules do not have an overall electric charge

(show this to sir + spec.)

Simple covalent molecules do not have any delocalised electrons or ions so it cannot carry a charge through the simple molecular (covalent) structure

Question 25

Explain why simple covalent molecules have low boiling and melting points

Answer 25

Simple covalent molecules have weak intermolecular forces. The weak intermolecular forces between the molecules do not require a lot of energy to break, therefore simple covalent molecules have low melting and boiling points.

Question 26

State the simple covalent molecule which is a liquid at room temperature

Answer 26

Water

Question 27

State the simple covalent molecules which are a gas at room temperature

Answer 27

Ammonia
Oxygen
Nitrogen
Methane
Hydrogen Chloride
Chlorine
Hydrogen
Carbon dioxide

Question 28

The weak forces between each molecule of a simple covalent molecules are called __________

Answer 28

The weak forces between each molecule of a simple covalent molecules are called intermolecular forces.

Question 29

The atoms in each molecule are held together by _________

Answer 29

The atoms in each molecule are held together by STRONG covalent bonds

Question 30

Substances that consist of small molecules are usually _________or _________________

Answer 30

Substances that consist of small molecules are usually gases or liquids

Question 31

What do small covalent structures have between the molecules

Answer 31

These substances have only weak forces between the molecules (intermolecular forces)

Question 32

When a simple covalent molecule melts or boils, what is overcome

Answer 32

It is these intermolecular forces that are overcome, not the covalent bonds, when the simple covalent molecule melts or boils.

Question 33

Why do larger simple covalent molecules have higher melting and boiling points

Answer 33

The intermolecular forces increase with the size of the
simple covalent molecules, so larger molecules have higher melting and boiling points as the intermolecular forces increase and require more energy to break.

Question 34

Describe the trend with the intermolecular forces and size of simple covalent molecules

Answer 34

The intermolecular forces increase with the size of the molecules

Question 35

What do larger, simple covalent molecules have that smaller, simple covalent molecules do not have

Answer 35

Larger simple covalent molecules molecules have higher melting and boiling points.