I'm not entirely sure but i think it's Se2-
The mass of Hydrogen is 2 g/mol
The mass of Helium is 4 g/mol
10 electrons
Explanation:
The maximum number of electrons in a single d-subshell is 10 electrons.
The d-sub-orbital used to denote azimuthal or secondary quantum numbers.
The maximum number of electrons in the orbitals of sublevels are:
two electrons in the s-sublevel, it has one orbital
six electrons in the p-sublevel, it has three orbital
ten electrons in the d- sublevel, it has five orbitals
fourteen electrons in the f-sublevel, it has seven orbitals
The maximum number of electrons in an orbital is two.
learn more:
Atomic orbitals brainly.com/question/1832385
#learnwithBrainly