structure and bonding exam questions

Question 1

Ionic bonding meaning

Answer 1

Electrostatic attraction between oppositely charged ions

Question 2

anomalous properties of water (3)

Answer 2

Ice is less dense than water - forms an open lattice
Unusually high MP/BP - hydrogen bond
High surface tension/viscosity - strength of H bonds across surface

Question 3

Ba(OH)2(aq) H2SO4(aq) → BaSO4(s) 2H2O(l)
The electrical conductivity of the solution steadily decreased as the sulphuric acid was
added.
Explain why the electrical conductivity decreased

Answer 3

The original solution contains ions

Charge carriers removed as the reaction takes place

Question 4

Explain why BP increases from sodium to aluminium

Answer 4

Charge density increases

Question 5

Why can’t water conduct electricity

Answer 5

Doesn’t have any free charge carriers

Question 6

Metallic bonding meaning

Answer 6

Delocalised electrons attracted to positive ions. Electrostatic attraction

Question 7

Why does Br2 have a higher boiling point than NH3

Answer 7

The boiling point of these substances determined by strength of intermolecular bonding. Van der wal forces in BR2 is greater than hydrogen bonding in NH3

Question 8

What structure is silicon dioxide

Answer 8

Giant covalent lattice

Question 9

What is the meaning of orbital

Answer 9

A region within an atom that can hold up to 2 electrons with opposite spin