In the reaction 3H2 + N2 → 2 NH3, what coefficient should be placed in front of NH3 to balance the reaction?

A) 1

B) 2

C) 3

D) no coefficient is needed

Suppose you discovered a new element with 120 protons and 2 electrons in its outer level . i'm what group does this new element belong? what properties would you expect it to have