A substance has a pH of 4. Is it an acid or a base?

Neils bohr believed that electrons orbited the nucleus in different energy levels, based on strong support from

Which statement correctly describes metallic bonds? a. they form when certain atoms lose electrons and other atoms gain electrons. b. they involve an attraction between anions and cations. they always involvpoth a metal and a nonmetal. d. they can only form between atoms of the same element. e. they form because electrons can move freely between atoms.

Answer asap need by wednesday morning calculate the ph of 0.036m naoh best answer will be brainliest