Which Element has the largest atomic radius
The Correct Answer and Explanation is :
The element with the largest atomic radius is francium (Fr).
Explanation:
Atomic radius refers to the size of an atom, typically measured from the nucleus to the outermost shell of electrons. The atomic radius increases down a group (column) in the periodic table and decreases across a period (row) from left to right. This trend is due to several factors, including electron shielding and the effective nuclear charge.
As you move down a group, additional electron shells are added. For example, francium is located in Group 1 (the alkali metals) and is at the bottom of the group. As a result, it has more electron shells compared to its lighter counterparts, such as lithium and sodium. This increase in distance from the nucleus means that the outermost electrons are further away, leading to a larger atomic radius.
Conversely, as you move from left to right across a period, the number of protons in the nucleus increases, which increases the nuclear charge. This stronger attraction pulls the electron cloud closer to the nucleus, resulting in a smaller atomic radius. Thus, while francium has the largest atomic radius among all elements due to its position in Group 1, elements like helium, which is at the top right of the periodic table, have the smallest atomic radius.
The large atomic radius of francium also makes it highly reactive. As an alkali metal, francium readily loses its outermost electron, contributing to its high reactivity. However, francium is extremely rare and radioactive, which complicates its study compared to more stable elements like sodium or potassium.
In summary, francium’s large atomic radius is primarily due to its position in the periodic table, being in the lower part of Group 1, leading to a greater number of electron shells compared to other elements.