Chem help

[Enderman]

Hi, can someone smarter than me confirm that this is a possible question?

 

¿? is an unknown non-metal (there are two possible answers to this question)

Im trying to come up with a question for my chem course, and I´m trying to make it a bit complicated.

 

 

So how I solve it is

count up all the electrons in the molecule (each bond counts as 2 electrons)

total is 30 electrons

the molecule has a - charge so the total of all the atoms is 29 electrons

find the valence electrons of each atom in the molecule

O=6

H=1

N=5

S=6

subtract the electrons of all the elements from the total electrons to find valence electrons of ¿?

29-6-6-5-6-1-1=4

 

this means ¿? has 4 valence electrons

if ¿? is a non-metal that means it is either C or Si

 

did I do it correctly? thanks