Answer:
d) None of the statements is true.
Step-by-step explanation:
(1) FALSE.
The valence electrons are the electrons from the valence shell. For the electron configuration given, the valence shell is 2s²2p², so there are 2 electrons in subshell 2s, and 2 electrons in subshell 2p, then there are 4 valence electrons.
(2) FALSE.
To form an ionic compound, first we put the cation and then the anion, and the charge of one is the amount of the other, so for Ba²⁺ and N³⁻, the compound is Ba₃N₂.
(3) FALSE.
The ion nitrate is NO₃⁻, and it has 4 atoms (1 N and 3 O) so it is tetratomic. The ion azide is N₃⁻, and it has 3 atoms, so it is triatomic.