Small question about atoms?

Question

Why is a sodium atom larger than a lead atom?

Answer 1

As you go from left to right along the periodic table the radii of element decrease in size (generally).

This is because stronger attractive forces in atoms between the opposite charges in the nucleus and electron cloud cause the atom to be 'sucked' together a little tighter.

Sodium is way over as a 1A group - so you would expect these interactions to be at a minimum - while Lead is a IVA group = smaller radius.

It's interesting to compare the two exerimentally derived radii - they aren't than far apart.

http://en.wikipedia.org/wiki/Lead
http://en.wikipedia.org/wiki/Sodium

Answer 2

A sodium atom is smaller than a Lead atom. Even though it decreases across the periodic table, it increases moving down the periodic table and the increase going down is a larger effect than the decrease going across. Each row of the periodic table represents another shell of electrons. Pb is about 2.5x larger than Na.

Answer 3

The nucleus of a Lead atom has a greater charge than a Sodium nucleus, therefore the electron cloud is held closer to the nucleus due to the stronger force.

Answer 4

because sodium atom has few electrons than lead meaning even though lead has many electrons they fill up the same shell about some # of electons( let us say 1st shell has 2 electons,2ndshell has 8 electrons.......). That's why sodium atom is larger than lead atom.

Answer 5

?? larger - lead is much larger in the nucleus.

Are you looking at the size of the electron orbitals. It's been to long... but I think sodiun would be having S orbitals and could be "looser" (less charge overall after all) letting the electrons fly a bit freeer.

Cant remember what kind of orbitals lead would use, but theve got to be throwing in all directions and sharing space with so many e- as lead has.