Which two terms relate and why? compound, ion, proton

Determine the wavelength of the light absorbed when an electron in a hydrogen atom makes a transition from an orbital in the n=3 level to an orbital in the n=7 level.

Which one of the following substances would be the most soluble in ccl4? na2so4 h2o ch3ch2ch2ch2oh c4h10 hi

Which liquid (h2o, h2o + soap, or h2o + salt) has the strongest cohesion and adhesion? (need now plz)