Is n2 + 3h2 →2nh3 a balanced chemical equation? is it obeying the law of conservation of matter?

Yes, this is a balanced chemical equation, and it obeys the Law of Conservation of Mass.

A balanced chemical equation obeys the Law of Conservation of Mass if there are the same numbers of each type of atom on each side of the reaction arrow.

N₂ + 3H₂ ⟶ 2NH₃

Let’s check the numbers.

Atom  On the left  On the right

   N            2                 2

   H            6                 6

We have the same numbers of H and O on each side of the reaction arrow.

The equation is balanced and it obeys the Law of Conservation

of Mass.

the electron configuration that you gave me has 16 electrons ergo it has 16 protons ergo it is the element sulfur.