Topic 2-bonding

Question 1

Dative covalent

Answer 1

-Donation of lone pair
-as the other element is electron deficient/only 6 outer shell electrons

Question 2

water and carbon dioxide

Answer 2

-oxygen more electronegative than carbon and hydrogen
-leaves a dipole
-carbon dioxide symmetrical so dipoles cancel out
-water has lone pairs and have a v shape

Question 3

thermal decomposition

Answer 3

-ionic and covalent bond
-strong bonds within ion
-produce co2 and one other product

Question 4

aluminium chloride and aluminium fluoride

Answer 4

aluminium chloride:
-small molecule
-weak London forces

Aluminium fluoride:
-fluorine more electronegative
-more polar bonds
-giant structure
-more E needed

Question 5

water and hydrogen fluoride

Answer 5

-More hydrogen bonds in water
-require more E

Question 6

Solubility of methanol in water

Answer 6

-OH group hydrogen bonds to water
-180 degrees
-strength of that hydrogen bond is greater than bonds between methanol molecules

Question 7

Solubility of chloroethene with water

Answer 7

-insoluble
-forms London forces and permanent dipole interactions with water

Question 8

Different solubilities

Answer 8

-insoluble in water as it doesn’t form hydrogen bonds
-soluble in hexane as London forces in both are similar in strength so resultant force is similar

Question 9

Metallic bonding

Answer 9

-regular lattice of positive cations
-sea of delocalised electrons
-strong electrostatic forces of attraction
-lots of E needed

Question 10

Factors affecting ionic bond strength

Answer 10

-as the charge of cation increase, stronger attraction-give example
-smaller the radius of cation, stronger attraction

Question 11

Phosphorus and nitrogen

Answer 11

-phosphorus can expand outer shell to have more than 8 electrons
-nitrogen can only have 8 on outer shell

Question 12

Bond angle

Answer 12

-lone pair-bond pair is greater than bond pair-bond pair

Question 13

Phosphorus chloride

Answer 13

both molecule and bond are polar

Question 14

Existence of ions in ionic bonding

Answer 14

In electron density maps nothing surrounds both cation and anion

Question 15

water and ice

Answer 15

-lattice
-h bond longer than covalent bond

Question 16

Magnesium

Answer 16

-neg charge is bigger than chlorine
-stronger attraction
-more E needed

Question 17

CO

Answer 17

dative covalent bond

Question 18

Dative covalent

Answer 18

-donation of e
-to an electron deficient species

Question 19

Ice

Answer 19

-more space between molecules
-due to lattice
-hydrogen bonds longer than covalent bonds

Question 20

F and Br

Answer 20

F more electronegative
due to less shielding
HF has greater dipole moment

Question 21

Propanone

Answer 21

Polar and non polar characteristics

Question 22

water and HF

Answer 22

Water has 2 hydrogen bonds per molecule so higher bp

Question 23

CO2

Answer 23

Polar bonds so absorbe IR radiation