Which of these statements best explains why pure water has a ph of 7?
1) pure water contains only h20 molecules, but ph is based on the concentration of h30+ ions.
2)each molecule of water can dissociate to form 7 h30+ ions.
3) water self-ionizes to form an equilibrium system that has [h30+]=1.0x10^-7m

Si una estrella no tiene paralaje medible, ¿qué puedes inferir?

The image shows a process that releases nuclear energy which statement best identifies the process shown the process must be fusion because energy is released the process must be fusion because of have your nucleus formed a smaller nuclei the process must be fission because a large nucleus breaks into smaller nuclei the process must be fission because neutrons are formed

Why does earth rotate? because earth is formed from cold gases collapsing due to gravity because the matter in the nebula that formed earth was spinning because earth forms more than 99% of the mass of the solar system because the hydrogen atoms inside the nebula fused to form helium