What is the Difference Between Bromine and Iodine?

06/24/2025 • Felipe Moraes

Bromine and iodine are both halogens found in group 17 of the periodic table of elements. They share some similarities, but there are key differences between them:

Physical State: Bromine is a liquid at room temperature, while iodine is a solid at room temperature.
Atomic Number: Bromine has an atomic number of 35, while iodine has an atomic number of 53.
Melting Point: Bromine has a melting point of -7.2°C, while iodine has a melting point of 113.7°C.
Boiling Point: Bromine has a boiling point of 58.8°C, while iodine has a boiling point of 184.4°C.
Reactivity: Bromine is more reactive than iodine but less reactive than chlorine.
Oxidizing Agent: Bromine can remove electrons from iodide ions, producing iodine, while iodine cannot.

Both elements have 7 valence electrons and are composed of nonmetals. They share a -1 oxidation state, are less reactive than fluorine and chlorine, and have a similar electronic configuration.

Comparative Table: Bromine vs Iodine

Here is a table comparing the differences between bromine and iodine:

Property	Bromine	Iodine
Electron Configuration	[Ar] 3d^10 4s^2 4p^5	[Kr] 4d^10 5s^2 5p^5
Position in Periodic Table	Group 17 and period 4	Group 17 and period 5
Melting Point	-7.2°C	113.7°C
Boiling Point	58.8°C	184.4°C
Physical State	Liquid at room temperature	Solid at room temperature
Appearance	Dark brownish-red liquid	Black-shiny crystalline solid
Vapor	Forms brown-colored vapor when boiled	Forms violet-colored vapor when boiled

Bromine and iodine are both halogens, meaning they are located in Group 17 of the periodic table. They both have 7 electrons in their outermost shell, but iodine is a larger atom. Bromine is a liquid at room temperature, while iodine is a solid.