As you look at the periodic table of elements, what trend or pattern do you notice about the size of each element’s atomic radius?
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As you move from left to right across a period on the periodic table, the atomic radius tends to decrease. This is because as you move from left to right, the number of protons and electrons in the atom increases, causing a greater attraction between the positively charged nucleus and the negatively charged electrons, pulling them closer together and resulting in a smaller atomic radius.
However, as you move down a group on the periodic table, the atomic radius tends to increase. This is because as you move down a group, each element has an additional electron shell, which increases the distance between the nucleus and the outermost electron, resulting in a larger atomic radius.
Overall, the trend for atomic radius is that it tends to decrease as you move across a period from left to right, and increase as you move down a group on the periodic table.