What kind of musical techniques did Mozart use for his requiem song Lacrimosa?

I mean if you named all those things can't you identify some examples yourself....just get a copy of the music and start with the basics....form.....language....number of voices...key and time signature...look for changes in texture in the voice parts...look for repeats...chromatic scales? no prob...look for sharps, naturals and flats ascending up or down... i mean just look over the music and things will start popping out at you..