What periodic trends exist for atomic radii?

Answer 1

As you move across a row on the Periodic Table, the atomic radii becomes smaller due to the attraction between positive protons and negative electrons. As you move down a column, the radii increase due to the addition of valance electrons.

Answer 2

Atomic radii generally decrease across a period from left to right due to increased effective nuclear charge pulling electrons closer to the nucleus. Within a group, atomic radii increase going down the group as additional energy levels are added, leading to increased electron shielding and less pull from the nucleus.

Answer 3

From left to right across a period, atomic radius goes down (even though atomic number goes up.) From top to bottom down a group, atomic radius goes up (because you're adding a principal energy level.) This trend, along with most of the others, has to do with the amount of attraction between the positively charged nucleus and the negatively charged electron cloud.

Answer 4

The periodic trend that occurs for atomic radius is that they decrease as you move from left to right.

Answer 5

In the periodic table of elements, atomic radius decreases slowly as you go from left to right in a period, and it increases rapidly as you go from top to bottom in a group.