The size will be H- ion > H atom > H+ ion
an insulator
Since Selenium is in the same column as Oxygen and Sulfur, you would expect it to bond just like them. As a halogen, chlorine wants to make one bond so your final answer would be. Cl-Se-Cl with two lone pairs (that's 4 electrons) on selenium and 3 lone pairs (that's six electrons) on EACH chlorine.
Larger
Any atom in the first family of the periodic table of elements is very unstable.
pretty much everything is larger than an atom.
that the nucleus of the atom was a lot larger than we now believe but the charge was not as spread out as you would expect.
A tetrahedron.
Tantalum
an insulator
Since Selenium is in the same column as Oxygen and Sulfur, you would expect it to bond just like them. As a halogen, chlorine wants to make one bond so your final answer would be. Cl-Se-Cl with two lone pairs (that's 4 electrons) on selenium and 3 lone pairs (that's six electrons) on EACH chlorine.
Larger
It would have 4 protons.
A metallic bond.
The francium atom is larger.
The francium atom is larger.
92 protons.
Any atom in the first family of the periodic table of elements is very unstable.