F321: Structure And Bonding

Question 0

Delocalised electron

Answer 0

Electron not belonging to any particular atom

Question 1

Lattice

Answer 1

Regular 3-D pattern of arrangement of particles, present in solids.

Question 2

Giant

Answer 2

Billions and billions of particles can make up the structure, no fixed number in the structure.

Question 3

Attractive force that breaks in giant metallic is between…

Answer 3

Cations and delocalised electrons

Question 4

Attractive force that breaks in giant ionic is between…

Answer 4

Oppositely charged ions

Question 5

Attractive force that breaks in giant covalent is between…

Answer 5

Atoms

Question 6

Attractive force that breaks in simple molecular is between…

Answer 6

Molecules

Question 7

Metallic bonding

Answer 7

The electrostatic attraction between cations and negative delocalised outer shell electrons

Question 8

Trends in metallic melting points across period

Answer 8

Eg Mg mpt > Na mpt
Magnesium ions have a greater charge and more delocalised electrons so there is a greater attraction between ions and electrons thus has stronger metallic bonds.

Question 9

Ionic bonding

Answer 9

The electrostatic attraction between oppositely charged ions

Question 10

Ionic substance solubility

Answer 10

Dissolve in polar solvents such as water due to formation of ion-dipole interactions (charged ions attracted by dipoles in water)

Question 11

Covalent bonding (not a covalent bond)

Answer 11

The electrostatic attraction between shared pair of electrons and a +ve nuclei

Question 12

Metal oxide + water ->

Answer 12

Metal hydroxide

Question 13

Uses of metal hydroxides

Answer 13

Ca(OH)2 used in agriculture to neutralise acidic soils

Mg(OH)2 used in indigestion tablets to neutralise stomach acids

Question 14

Metal carbonates (+heat) ->

Answer 14

Metal oxide + carbon dioxide

The heat/temperature to bring about thermal decomposition increases down the group (therefore thermal stability increases down group)

Question 15

Displacement reactions

Answer 15

A more reactive halogen displaces a less reactive halogen from a solution of its salt
Can be used to determine relative reactivity of halogens

Question 16

Test for halide ions

Answer 16

1) add HNO3
2) add aqueous silver nitrate (AgNO3)
- > white ppt- AgCl
- > cream ppt- AgBr
- > pale yellow ppt- AgI

Note: excess nitric acid added to destroy any corbonate impurities which could form a precipitate which would mask the true colour.

Question 17

Reaction of Chlorine with water (to purify)

Answer 17

Cl2 (aq) + H2O (l) -> HCl (aq) + HClO (aq)

Question 18

Reaction of Chlorine with NaOH (manufacture of bleach)

Answer 18

Cl2 (aq) + 2NaOH (aq) -> NaCl (aq) + NaClO (aq) + H2O

Question 19

Reaction where one element is both simultaneously oxidised and reduced

Answer 19

Disproportionation

Question 20

Benefits of Cl2

Answer 20

Treatment of water (kills bacteria)

Question 21

Hazards of Cl2 in water

Answer 21

Cl2 gas is a toxic gas, chlorinated hydrocarbons can form which can be carcinogenic.
Health/safely: wear gloves when handling toxic substances.