First year math units are definitely scaled, i'm 90% sure that i barely passed in terms of raw marks for MATH1902 or even failed and ended up getting a distinction.
There's no scaling for CHEM1901, but they make it so it's almost impossible to fail and tbh, most questions aren't very difficult.
Biology, i don't believe is scaled, since the exam is the same whether your doing regular, advanced or SSP. (save a few prac multiple choice)
If you had the option to do PHYS1901 or PHYS1001 do PHYS1901, some of the exam questions are actually easier than the ones in PHYS1001 + it's scaled.