What is the Physical State of Iodine at Room Temperature?

Answer: At room temperature (around 25 °C), iodine exists as a shining, dark grey solid. Iodine is a non-metal. Nevertheless, its crystals sparkle like metals due to their shiny, flat surfaces, similar to tiny mirrors. Iodine is made up of pairs of atoms (I₂). In solid form, these pairs would stick together and form a pattern called a molecular lattice. These molecules are held together by weak forces called van der Waals forces. These forces have enough strength to hold iodine together till it gets hot-above 113.7 °C. In this article, we will understand the answer to your question:’’ What is the Physical State of Iodine at Room Temperature?’’ in depth.

Sublimation: Iodine’s Spectacular Disappearance Act

The physical State of Iodine at room temperature is a dark grey solid. Even though it’s solid, iodine is known for one special trick called sublimation.  When you heat iodine crystals in an open container, you will find that they won’t melt into a liquid like other substances. Instead, they directly transform from solid to gas, and skip the liquid phase. The gas will be in deep purple, and comes from iodine molecules. This change is interesting to watch and, therefore, is a popular experiment in chemistry class.

Why Solid Iodine Is Important in the Lab?

The physical State of Iodine at room temperature is a dark grey solid.  This solid iodine is important in a lab for many reasons. Some of these reasons include:

1. Storing Iodine: Iodine, when kept at room temperature, can slowly turn into vapour. Therefore, it must be kept in a closed container. This prevents it from turning into gas, and protects you from its strong smell.
2. Making Iodine Solutions: Chemists add potassium iodide (KI) to dissolve iodine in water. KI helps to create a brown solution called triiodide (I₃⁻) that can stay dissolved easily. Thus, iodine is prevented from turning into vapour quickly.
3. Purifying Iodine: The ability of the iodine to turn directly into gas is also useful while clearing it up. If you simply heat the impure iodine, it will turn into vapour and leave the impurities behind.  Thereafter, the pure iodine cools down and forms clean crystals again on a cooler surface.

A Glimpse into the Halogen Family

Iodine is a part of a group of elements called halogens. Halogens come under Group 17 on the periodic table. Its family consists of:

1. Fluorine and chlorine (gases)
2. Iodine  (a solid)
3. Bromine (a liquid)
4. Astatine (a rare and radioactive element)

This group helps you understand that as atoms get bigger, they often change from gas to liquid to solid. This is an example of how the size of atoms and the forces between molecules can affect how the substances behave.

Common Reads:

What is the Chemical Name of Iron?	What is an Inflammable Substance?
What are Eka-Boron, Eka-Aluminium and Eka-Silicon?	What are the first 30 elements and their symbols?
When metals and non-metals other than oxygen react, what is formed?	Who is known as the Father of Indian Chemistry?