What keeps galaxies togther? How?

Five students had to answer the question how are elements arranged in a periodic tabledamon: i think the elements are arranged by increasing massflo: i think the elements are arranged according to their properties sienna: i think the elements are arranged by when their discovers kyle: i think the elements are arranged according to how common they areglenda: i don't agree with any of themwho is right

When water dissociates, each water molecule splits into a hydroxide ion and a) h 3 o + b) a hydrogen atom c) a hydrogen ion d) h 2 o e) oh —

Amixture with the same composition throughout is!