States of matter
I The gaseous state:
(i) Ideal gas behaviour and deviations from it
(ii) pV = nRT and its use in determining a value for Mr
II The liquid state
The kinetic concept of the liquid state and simple kinetic-molecular descriptions of changes of state
III The solid state Lattice structures
Learning outcomes Candidates should be able to:
(a) state the basic assumptions of the kinetic theory as applied to an ideal gas
(b) explain qualitatively in terms of intermolecular forces and molecular size:
(i) the conditions necessary for a gas to approach ideal behaviour
(ii) the limitations of ideality at very high pressures and very low temperatures
(c) state and use the general gas equation pV = nRT in calculations, including the determination of Mr
(d) *describe, using a kinetic-molecular model: the liquid state, melting, vaporisation, vapour pressure
(e) *describe, in simple terms, the lattice structure of a crystalline solid which is:
(i) ionic, as in sodium chloride, magnesium oxide
(ii) simple molecular, as in iodine
(iii) giant molecular, as in silicon(IV) oxide and the graphite and diamond allotropes of carbon
(iv) hydrogen-bonded, as in ice
(v) metallic, as in copper
[the concept of the ‘unit cell’ is not required]
(f) explain the strength, high melting point and electrical insulating properties of ceramics in terms of their giant molecular structure
(g) relate the uses of ceramics, based on magnesium oxide, aluminium oxide and silicon(IV) oxide, to their properties (suitable examples include furnace linings, electrical insulators, glass, crockery)
(h) describe and interpret the uses of the metals aluminium (including its alloys) and copper (including brass), in terms of their physical properties
(i) understand that materials are a finite resource and the importance of recycling processes
(j) outline the importance of hydrogen bonding to the physical properties of substances, including ice and water
(k) suggest from quoted physical data the type of structure and bonding present in a substance