Por favor ayudenme con esto, tema es compuestos orgánicos oxigenados

If a polyatomic ionic compound has gained two hydrogen ions, then how does its name begin?

What are the first two quantum numbers for the electrons located in subshell 4d? what are the first three quantum numbers for the electrons located in subshell 2s? how many electrons can be held in a sublevel l = 3? how many electrons can be held in the energy level n = 4? how many electrons in an atom can share the quantum numbers n = 4 and l = 3?

What is the percentage of hydrogen in nitrogen trihydride