Which element has a larger atomic radius? k or caexplain

Potassium (K) has a greater atomic radius than that of Calcium (Ca) because when we move down a group, the atomic radius increases and when we move from left to right in a period, the atomic radius decreases.

Explanation

Both potassium and calcium belong to the 4th period in the periodic table of chemical elements. So, we cannot judge thier atomic radius by their group now, so we have to look at which element to to the left of the other. Here in this case we see potassium is on the left to calcium. So, the atomic radius of potassium (K) is greater than that of calcium (Ca).

Hope this answer correct :)

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.