Chemistry
Principles of chemistry
States of matter
1.1 understand the three states of matter in terms of the arrangement, movement and energy of the
particles (SMAF)
● Solid:
○ Shape- fixed shape + volume
○ Movement- vibrate about a fixed position
○ Arrangement - regular, close together touching each other
○ Forces between particles- stronger than in a liquid
● Liquid:
○ Shape- no fixed shape but fixed volume
○ Movement- move around and slide past one another
○ Arrangement- irregular, close together touching each other
○ Forces between particles- not as strong as solid
● Gas:
○ Shape- no fixed shape + volume
○ Movement- freely and collide with each other
○ Arrangement- irregular, far apart
○ Forces between particles- non existent
1.2 understand the interconversions between the three states of matter
Melting and freezing take place at the melting point
● Solid to liquid: melting
● Liquid to solid : freezing
Boiling and condensing take place at the boiling point
● Liquid to gas: boiling
● Gas to liquid: condensing
Liquid to gas
● Liquid heated = particles gain KE + move further apart= attractive forces in the liquid
are broken.
, Solid to liquid
● Solid heated gains KE + vibrates faster, temperature high enough= vibration becomes
enough to overcome forces of attraction between them.
Liquid to solid
● Cool until it freezes=particles lose KE. Temperature low enough=particles no longer
have energy to slide over each other = forces hold particles together
Gas to liquid
● Cool until it condenses = particles lose KE + attractive forces become great enough to
keep particles closer together
Solid to gas
● Heat solid until it sublimes. Particles gain KE + vibrate faster. Eventually forces of
attraction between particles= broken
1.3 understand how the results of experiments involving the dilution of coloured solutions and
diffusion of gases can be explained
Diffusion- Movementofparticlesfromanareaofhighconc. toanareaof lowconc.
● Forthistowork,particlesmustbeabletomove. Therefore,diffusiondoesnotoccurin
solids,sincetheparticles cannotmovefromplacetoplace(onlyvibrate)=coloured
solutionsaredilutedbyaddingwater,bc the particlesofthecolourdiffusetotheair
oflowconcentration,mixingwith thewatermolecules,causingdilutiontooccur
1.4 know what is meant by the terms:
Solvent: liquid in which a solute dissolves
Solute: substance which dissolves in a liquid to form solution
Solution: mixture formed when a solute is dissolved in a solvent
Saturated solution: solution with the maximum conc. of solute dissolved in the solvent
1.5C know what is meant by the term solubility in the units g per 100 g of solvent
Solubilityisshownasthegramsofasolutethatwilldissolvein100gofwater
1.6C understand how to plot and interpret solubility curves
Elements, compounds and mixtures
1.8 understand how to classify a substance as an element, compound or mixture
● Element=substancemadefromonlyonetypeofatom
● Compound=substancemadefromtwoormoreelementsthathavereacted
chemicallywitheachother
● Amixture:
○ Consistsof2ormoreelementsorcompoundsnotchemicallycombined
together
○ Chemicalpropertiesofeachsubstanceinthemixtureareunchanged
Principles of chemistry
States of matter
1.1 understand the three states of matter in terms of the arrangement, movement and energy of the
particles (SMAF)
● Solid:
○ Shape- fixed shape + volume
○ Movement- vibrate about a fixed position
○ Arrangement - regular, close together touching each other
○ Forces between particles- stronger than in a liquid
● Liquid:
○ Shape- no fixed shape but fixed volume
○ Movement- move around and slide past one another
○ Arrangement- irregular, close together touching each other
○ Forces between particles- not as strong as solid
● Gas:
○ Shape- no fixed shape + volume
○ Movement- freely and collide with each other
○ Arrangement- irregular, far apart
○ Forces between particles- non existent
1.2 understand the interconversions between the three states of matter
Melting and freezing take place at the melting point
● Solid to liquid: melting
● Liquid to solid : freezing
Boiling and condensing take place at the boiling point
● Liquid to gas: boiling
● Gas to liquid: condensing
Liquid to gas
● Liquid heated = particles gain KE + move further apart= attractive forces in the liquid
are broken.
, Solid to liquid
● Solid heated gains KE + vibrates faster, temperature high enough= vibration becomes
enough to overcome forces of attraction between them.
Liquid to solid
● Cool until it freezes=particles lose KE. Temperature low enough=particles no longer
have energy to slide over each other = forces hold particles together
Gas to liquid
● Cool until it condenses = particles lose KE + attractive forces become great enough to
keep particles closer together
Solid to gas
● Heat solid until it sublimes. Particles gain KE + vibrate faster. Eventually forces of
attraction between particles= broken
1.3 understand how the results of experiments involving the dilution of coloured solutions and
diffusion of gases can be explained
Diffusion- Movementofparticlesfromanareaofhighconc. toanareaof lowconc.
● Forthistowork,particlesmustbeabletomove. Therefore,diffusiondoesnotoccurin
solids,sincetheparticles cannotmovefromplacetoplace(onlyvibrate)=coloured
solutionsaredilutedbyaddingwater,bc the particlesofthecolourdiffusetotheair
oflowconcentration,mixingwith thewatermolecules,causingdilutiontooccur
1.4 know what is meant by the terms:
Solvent: liquid in which a solute dissolves
Solute: substance which dissolves in a liquid to form solution
Solution: mixture formed when a solute is dissolved in a solvent
Saturated solution: solution with the maximum conc. of solute dissolved in the solvent
1.5C know what is meant by the term solubility in the units g per 100 g of solvent
Solubilityisshownasthegramsofasolutethatwilldissolvein100gofwater
1.6C understand how to plot and interpret solubility curves
Elements, compounds and mixtures
1.8 understand how to classify a substance as an element, compound or mixture
● Element=substancemadefromonlyonetypeofatom
● Compound=substancemadefromtwoormoreelementsthathavereacted
chemicallywitheachother
● Amixture:
○ Consistsof2ormoreelementsorcompoundsnotchemicallycombined
together
○ Chemicalpropertiesofeachsubstanceinthemixtureareunchanged
