Ionic, Covalent and Metallic bonding

Question 1

What is a covalent bond ?

Answer 1

the attraction between the bonding pair of electrons and (2+) atomic nuclei

Question 2

Why do metals conduct electricity ?

Answer 2

delocalised electrons, free to move from one side to the other. Thus conduct electricity. (flow of electrons)

Question 3

Why are metals malleable ?

Answer 3

Layers can slide, when they do the positive metal ions are in the same environment as they were, still electrostatic attraction.

Question 4

How does a Ionic bond differ to covalent ?

Answer 4

Ionic=m/nm covalent= nm/nm covalent=share electrons (no ions) ionic is opposite. (accept any other relevant answers)

Question 5

Why are ionic compounds brittle ?

Answer 5

when force is applied, a cation may rearrange and be next to another cation=repulsion=brittle.

Question 6

Name the attraction in a ionic lattice and why does it require so much energy to break up the lattice ?

Answer 6

electrostatic attraction, hard to overcome as it acts in all directions between anions and cations, requires lots of energy.

Question 7

What is a dative bond and what does the arrow mean ?

Answer 7

is a covalent bond in which 1 molecule provides both pairs of electrons(lone pair), arrow=direction in which the electrons are given, from the donor.

Question 8

Why can graphite conduct electricity and its layers slide ?

Answer 8

delocalised electrons and weak intermolecular forces between layers. (van der waal forces)

Question 9

Place the following in order of strength; metallic, covalent and ionic.

Answer 9

1)covalent 2) ionic 3) metallic

Question 10

name the types of crystal

Answer 10

molecular, ionic, covalent, metallic

Question 11

of the 4(crystals) which is iodine, and why is little energy needed to break its structure ?

Answer 11

molecular: weak van der waal forces between molecules

Question 12

what does crystalline and amorphous mean ?

Answer 12

crystalline= regular/neat fixed arranged pattern. Amorphous= no regular pattern

Question 13

what is the electrostatic attraction between in a covalent bond ?

Answer 13

nuclei of atoms and bonding pair of electrons

Question 14

why do no ions form ?

Answer 14

only involves sharing of electrons

Question 15

give an example of a giant covalent structure + why high melting point

Answer 15

diamond: 4x covalent bond per C, giant covalent, lots of energy required