The answer is C) [Ar]4s2 3d6
I believe it’s loses two electrons.
Se2- has 34 protons and 36 electrons so it gets a 2- charge.
Answer: 
Explanation:
Molecular formula is the chemical formula which depicts the actual number of atoms of each element present in the compound.
Empirical formula is the simplest chemical formula which depicts the whole number of atoms of each element present in the compound.
The empirical formula is 
The empirical weight of
= 1(12)+1(1)+1(16)= 29 g.
The molecular weight = 60 g/mole
Now we have to calculate the molecular formula:

The molecular formula will be=
Thus molecular formula will be 
Answer:
A covalent chemical bond is one in which <u>outer-shell electrons of two atoms are shared so as to satisfactorily fill their respective orbitals</u>.
Explanation:
Covalent bonds are formed between two atoms having their electronegativity difference less than 1.7. In this type of bonding the valence electrons of one atoms forms molecular bond with the valence electrons of another atom. The electrons are mutually shared.
Covalent bond can be non-polar as for example formed between hydrogen and carbon atoms.
Also, covalent bond can be polar in nature as that formed between hydrogen and chlorine atoms because the chlorine atom is more electronegative and hence attracts the electrons more towards itself making density of electrons less on hydrogen atom.