Bromine is farther down the group and has more electron shells, making it an element with a lager atomic radius.
bromine
Fluorine
Basically, the more electrons that are present in an atom, the more elctron shells it will have. Look at a periodic table and you'll see Astatine has a proton number of 85 (85 protons), as the number of electrons and protons is equal, we can therefore deduce that it has 85 electrons and is the largest halogen atom. Therefore astatine MUST have the most electron shells as it has more electrons to fill them. Basically, the more electrons that are present in an atom, the more elctron shells it will have. Look at a periodic table and you'll see Astatine has a proton number of 85 (85 protons), as the number of electrons and protons is equal, we can therefore deduce that it has 85 electrons and is the largest halogen atom. Therefore astatine MUST have the most electron shells as it has more electrons to fill them.
silicon
As a general rule atomic radius decreases as you read across a period, so from largest to smallest the order would be Li, B, C, F.
bromine
bromine
Chlorine.
fluorine-0.824,chlorine-0.479,bromine-0.474,iodine-0.214 joule/gram kelvin
Chlorine will have the smallest atomic radius, bromine the largest.
Fluorine
francium has the largest ionic radius
12-Magnesium
Fluorine has the largest first ionization energy among the halogens.
F (fluorine) is the largest and heaviest (atomic number 9). Boron, nitrogen, and oxygen are numbers 5, 7, and 8.
Astatine, with a molecular weight of 210 amu.
Fluorine (F): 4.0 Oxygen (O): 3.5 Nitrogen (N) and Chlorine (Cl): 3.0