Question

Which element in row 6 of the periodic table (shown below) has the largest radius?

Answer 1

The element in row 6 of the periodic table that has the largest radius is Cs (Caesium), with atomic radius of 260pm. 
Caesium is chemical element with atomic number 55.

Answer 2

The answer would be Caesium (Cs).

The periodic trend of atomic radius is that it increases as you move down the periodic table and and to the the left. So since we are looking at Period 6, we look at it horizontally. Cesium is found in the left-most side of the period, so it has the largest atomic radius.