Covalent Bonding

Question 1

Types of bonds broken- N2->N2

Answer 1

Dispersion forces

Question 2

Types of bonds broken-hg->hg

Answer 2

Metallic bonds

Question 3

Types of bonds broken- 2NaCl-> 2NA+CL2

Answer 3

Ionic bonds

Question 4

Hydrogen bonding

Answer 4

Can only occur with oxygen,florine and Nitrogen

Question 5

A typical feature of covalent molecular substances

Answer 5

They are gases, liquids or soft, low melting point solids at room temperature

Question 6

Type of Bond must be broken for water to vaporise

Answer 6

Hydrogen bonds only

Question 7

Difference between ionic and molecular substances

Answer 7

Do not conduct In the molten state, whereas ionic substances do

Question 8

Why do H:Y:H and .. not have the same shape H :Z:H ..

Answer 8

Because Element Y has 2 lone pairs which are not included in the lewis diagram whereas Z has no lone pairs. Y would perfrom a Linear shape where Z is a tetrhdyral shape because Y is a group 16 atom and Z is a group 14 atom

Question 9

Ethanol (CH3Ch2Oh) has a

Answer 9

A High melting point

Question 10

Graphite is

Answer 10

Brittle

Question 11

Methane (Ch4) does not

Answer 11

Conduct electricity in the solid or aqueous state

Question 12

Polar Molecule

Answer 12

When a stronger attraction comes from the element with a higher electronegativity. Must have different electronegatvity and or an incomplete turnaround

Question 13

Non Polar Molecule

Answer 13

Molecular elements are always non polar because they have the same electronegativty

Question 14

Why are Molecular compounds sometimes polar and non polar?

Answer 14

It depends on their electronegativity. It also depends on the shape of the molecule as well on bond dipoles. If the bond dipoles cancel out then it will be non polar

Question 15

The intramolecular and intermolecular forces in water

Answer 15

Dipole dipole, hydrogen bonding and dispersion forces

Question 16

Why is the density of ice less than the density of water

Answer 16

Because the regular arrangments of the water molecules in ice take up more space than the irregular arrangment of molecules in liquid

Question 17

What is a Covalent bond?

Answer 17

A bond that exists with only non metals. Neighbouring atoms share electrons to achieve a full outer shell. Atoms try to achieve a stable noble gas config of 8 outer shell electrons

Question 18

What are the physical properties associated with covalent bonding?

Answer 18

Do not conduct electricity because the molecules are electrically neutral, Vary in their solubility (Polar compounds are soluble in polar solvents such as water but in soluble in non polar solvents), Have low boiling and melting points since the forces between them are weak.

Question 19

The trend in physical properties based in the intermolecular forces in operation?

Answer 19

?

Question 20

What type of bonding occurs between water in its different states?

Answer 20

Hydrogen bonding, Di-dipole bonds and dispersion forces

Question 21

Water in liquid

Answer 21

Water molecules move too quickly in liquid form to form regular structures however they still remain attacthed.

Question 22

Water being frozen

Answer 22

Water molecules expand when frozen. Water molecules join together to form hexagonal structures