I think early teens and pre-teens can be very volatile.
Living with them can be very hard 
Is she growing very fast atm? My dd grew 8 cms last year (they have a growth spurt prior to periods starting apparently) and if they are growing fast they often have a parallel burst of hormones which can adversely affect their behaviour.
And starting a new school will have added to the mix - even if she is happy there - it's a big change.
I'm no expert but I think the bleach thing sounds like a manifestation of anxiety. I think a lot of pre-teens/early teens are anxious and this comes out as "flight" (ie shut down defensive) or "fight" (perceive everything as an attack - even mildest of rebukes - fight back).
I have to bite my tongue a lot with mine and really choose my moment when I talk to her about something difficult.
These books have helped:
"How to talk so teens will listen and listen so teens will talk" by Adele Faber and Elaine Mazlish
"Get out of my life" "But first take me and Alex in to Town" by Tony Wolf and Suzanne Franks
"Blame my Brain" by Nicola Morgan
Do you have lots of limits re: screen time by the way? (Mine has just had all technology removed for a month for a totally different reason and the transformation in her has been miraculous to see: less eye-rolling, more enthusiasm for life, more willing and compliant, happier, marks have gone up!)
Is she getting enough sleep?
If she's behaving well at school then I guess she considers home her safe place, and you her safe person! It is very hard. Good luck with it all!