Please help, it's a task in science and I'm really bad at this subject.

Astudent carefully transfers 30 g of water and 30 g of alcohol in a glass tube, forming two layers and filling the tube completely. after sealing the tube, the student mixes the solutions, and notices a bubble that forms in the tube. what is the mass of the contents in the glass tube after mixing?

Word equation for k(s) +h2o(l) yield koh (aq) + h2

In which reaction is precipitation occurring?