(Original post by kitriviolet)
hey i did AS and got 300/300..i think there are things they always stick on the exam. just do some past papers..youll get used to the format. okay, i mean, do all the past papers as well as the sample assessment materials. its pretty much standard..unlike the system in hong kong. ugh. im doing that system and registering for GCE as a private candidate..i like GCE more. much more straightforward.
for unit 1 its good to memorize how to explain these things:
-factors affecting first ionization energy & reasons for trends across periods/down groups
-factors affecting extent of covalency in lattices
-factors affecting strength of metallic bond & trends across periods
-factors affecting lattice energy
-whats happening with successive ionization energies
-principle of mass spectrometer
-difference between risk & hazard, and also between precision & accuracy
-what is happening in born-haber cycles
-all the reactions of organic compounds
and of course, dont forget to swallow down how the mechanisms are drawn..and definitely the hess cycles. hess cycles are bound to come up..and mechanisms 80% of the time.
as for unit 2 you should learn to explain these:
-shape of molecules and ions (like the electron pairs maximize separation to minimize repulsion, blah blah blah)
-if one molecule is polar (like CCl4: it has polar bonds but as it is completely symmetrical, the molecule is non-polar overall)
-why something is a redox reaction (the oxidation numbers change) or why something isnt (no change in redox numbers)
-why sth is a disproportionation reaction (same species is oxidized and reduced simultaneously, then get on to describe the change in oxidation numbers)
-what happens to an equilibrium system
ok then also learn the reactions of group 2 and group 7 stuff. then also rmb the reaction mechanisms in unit 2..then memorize what are carbon footprint and carbon neutral. as well as the effects of various fuels/sprays/chemicals...etc on the atmosphere.
hope that helped (: if you need help, just find me