The answer 1) Oxygen. And another smallest radius is fluorine, because it is the first in the periodic table.
The correct answer is a metal atom forms a cation, and a nonmetal atom forms an anion. This is because metals are less electronegative than nonmetals and will therefore give electrons to nonmetals. Atoms that give up electrons will have a positive charge therefore becoming a cation while atoms that accept electrons will have a negative charge therefore becoming an anion.
Ions that have the same charge can't be attracted to each other since it takes a positive and negative charge to cause attractive forces.
A less electronegative atom will transfer electrons to a more electronegative atom.
A metal (cation) can pull electrons from another metal (not an ion) but that does not form an attractive force between the two metals (You will learn more about this when you go over reduction potentials, redox reactions, and electrochemistry).
I hope this helps. Let me know if anything is unclear.
The heat required to completely melt the given substance, platinum, we just have to convert first the given mass in mole and multiply the answer to its molar heat of fusion..
Hf = mass x (1/molar mass) x molar heat of fusion
Hf = (85.5 g) x (1 mole/195.08 g) x 4.70 kcal/mol
Hf = 2.06 kcal
