1.3 bonding

Question 1

definition of ionic bonding

Answer 1

the electrostatic attraction between oppositely charged ions in a lattice
metals + non metals

Question 2

ionic properties- MP+BP

Answer 2

strong electrostatic forces between oppositely charged ions in a giant lattice which needs lots of energy to overcome

Question 3

ionic properties- solubility in water

Answer 3

good because the 2 poles of water has strong forces of attraction to other charged ions, so it breaks the ionic bond by hydrogen bond formation

Question 4

ionic properties- conductivity

Answer 4

-can’t in solid as ions aren’t free to move in a lattice
-can when molten/aqueous as ions are free to carry charge

Question 5

ionic properties- brittleness

Answer 5

when layers of alternating charges are distorted, like charges repel which breaks the lattice apart

Question 6

definition of covalent bonding

Answer 6

shared pair of electrons between two atoms

Question 7

simple molecular properties- MP+BP

Answer 7

low due to weak van der waals forces which dont need lots of energy to overcome
water is simple molecular but has high MP+BP due to the presence of hydrogen bonding

Question 8

simple molecular properties- conductivity

Answer 8

poor as there are no ions to conduct electricity and electrons are localised- contains no charged particles

Question 9

macromolecular structure properties- MP+BP

Answer 9

high due to many strong covalent bonds which need lots of energy to overcome- each atom has multiple covalent bonds

Question 10

macromolecular structure properties- solubility in water

Answer 10

insoluble- they can’t form strong attractions with water

Question 11

macromolecular structure properties- conductivity

Answer 11

-when solid- diamond and sand cannot because electrons are localised, but graphite can as it has delocalised electrons free to carry charge

Question 12

definition of metallic bonding

Answer 12

electrostatic attraction between a lattice of positive metal ions and delocalised electrons

Question 13

metallic bonding properties- MP+BP

Answer 13

high- strong electrostatic forces between positive ions and sea of delocalised electrons

Question 14

what is the electron pair repulsion theory (3)

Answer 14

-the shape of a molecule depends on its electron structure- the valence electrons are responsible for forming bonds
-pairs of electrons will repel each other (- charge)
-pairs of electrons move as far apart as possible to minimise repulsion

Question 15

properties of linear molecules

Answer 15

-bonding pairs: 2
-lone electron pairs: 0
-bond angle: 180
-example: beryllium chloride

Question 16

properties of v-shaped molecules

Answer 16

-bonding pairs: 2
-lone electron pairs: 2 or 1
-bond angle: 104.5 or a little less than 120
-example: water

Question 17

properties of trigonal planar molecules

Answer 17

-bonding pairs: 3
-lone electron pairs: 0
-bond angle: 120
-example: boron trifluoride

Question 18

properties of pyramidal molecules

Answer 18

-bonding pairs: 3
-lone electron pairs: 1
-bond angle: 107
-example: ammonia

Question 18

properties of tetrahedral molecules

Answer 18

-bonding pairs: 4
-lone electron pairs: 0
-bond angle: 109.5
-example: methane

Question 19

properties of trigonal bipyramidal molecules

Answer 19

-bonding pairs: 5
-lone electron pairs: 0
-bond angle: 90 and 120
-example: phosphorus pentachloride

Question 20

properties of square planar molecules

Answer 20

-bonding pairs: 4
-lone electron pairs: 2
-bond angle: 90
-example: xenon tetrafluoride

Question 21

properties of seesaw molecules

Answer 21

-bonding pairs: 4
-lone electron pairs: 1
-bond angle: 89 and 119
-example: sulfur tetrafluoride

Question 22

properties of t-shaped molecules (trigonal bipyramidal with lone pairs)

Answer 22

-bonding pairs: 3
-lone electron pairs: 2
-bond angle: 88 (when lone pairs are next to each other) or 120 (when lone pairs are on opposite sides)
-example: chlorine trifluoride