How to deal with incompetent PhD student as an undergrad
No gloves/splash goggles when working with (hot) concentrated acids and bases. Some of these experiments are run outside the fume hood, and sometimes on the floor when there is no space on the lab bench.

Do not work in this lab.  Do not even go in.  It could kill you.  Obvious safety problems are often accompanied by even worse, hidden problems.
Consult your university's safety policy to determine if you can/should/must report this situation.
The other problems are insignificant by comparison.  Find a new PI.