Help i wanna go 2 sleep but this is due tmrw morning : If Oxygen (O) lost two protons what would it be?

Calculate the molar mass of aluminum oxide (al2o3). express your answer to four significant figures.

Which of the following has wavelength longer than the wavelength of viable light? a) x rays b) gamma rays c) radios waves d) ultraviolet waves

Consider hydrogen in an excited state n = 5n=5 that emits photons to reach the ground state. there are various possible transitions other than straight to the ground state that can occur; for example, it can drop to the n = 3n=3 state followed by the n = 3n=3 to the ground state transition. which of the possible transitions will result in the emission of a photon in the visible region?