Difference Between Chlorine and Chloride (with Table)

The periodic table currently has 103 elements. But as time goes by and the Earth is being dug up deeper, more and more elements are resurfacing. These elements of the periodic table were placed according to the atomic number that automatically arranged them according to their atomic mass as well.

The seventeenth element of the periodic table is chlorine. But often people tend to mistake chlorine as chloride as they sound similar and also have similar symbols. But what is the difference between the two?

Chlorine is the element of the periodic table with Cl as the symbol. The atomic number of chlorine is 17 and their atomic mass is 35.5. Chlorine is naturally found in the gaseous state and so it is a yellow-green gas. The first chlorine synthesis was done in 1683, but back then it was not fully considered as an element.

Chloride is the ionic state of chlorine that is formed when chlorine gains one electron. They are least/not electronegative as they have an inert gas configuration. They have the configuration of Argon as they have 18 electrons. Since they have 18 electrons and 17 protons, they are highly unstable and reactive.

The difference between Chlorine and Chloride is that while chlorine is an element of the periodic table with atomic number 17, chloride is the anion formed when chlorine gains one electron.

Comparison Table Between Chlorine and Chloride

Parameters of ComparisonChlorineChloride
Type of particleAn elementIt is an anion.
Natural formchlorine is a gas in its natural state.Chloride mostly occurs as a mineral supplement.
ColourYellow-ish green when in the gaseous state.Is colourless in an aqueous medium like all the other ions.
Number of electronsChlorine has 17 electrons and protons.Chloride has 18 electrons and 17 protons.
Inert ConfigurationThey are still in their elemental form. So inert configuration is not obtained.They are an ion with 18 electrons and have attained the electronic configuration of the inert gas, Argon.
ElectronegativityIt is the third-highest element in the electronegative series of elements.Though it is an ion of chlorine, it is less electronegative as it has an inert configuration.

What is Chlorine?

Chlorine is an element of the periodic table. It was first synthesized in 1683 as a gas. So their naturally occurring state is as a gas. But it wasn’t until 1810, that it was named a pure gas and given the name ‘chlorine’.

The name was given because of the yellowish-green colour of the gas as ‘khlorous’ stands for the green in Greek. They are highly electronegative and are the third-highest electronegative element in the periodic table.

So, they are good oxidizing agents. Since they are good oxidizing agents, they are also used in the bleaching industry. Apart from bleaching, they are also used as a disinfectant for purification of water and sanitization.

It is very difficult to find chlorine in its elemental form and is also very harmful. It is not to be consumed directly. Their rarity is also because of their reactivity that does not allow them to stay in their elemental form but rather as compounds with other elements.

What is Chloride?

Chloride is the anion of chlorine that is obtained on gaining one electron. It is represented by the symbol Cl. Chloride has 18 electrons and 17 protons in their atom.

This makes them highly unstable and reactive. So they are often found as salts with other ions like potassium chloride and calcium chloride. The most common form of chloride is as sodium chloride, which is the common salt.

Apart from salts, they are also a vital mineral that is needed for our body and is often found as mineral supplements. It is one of the major minerals that is found in our body. About 750-800 g of chloride are consumed by a human being.

The lack of chloride can lead to hyponatremia. This causes weakness in muscles and lethargy. But excess chloride is also not to be consumed as it leads to hypernatremia and dehydration.

Main Differences Between Chlorine and Chloride

  1. Though they may seem similar, they are different types of particles. Chlorine is an element belonging to the periodic table. On the other hand, chloride is an ion which is formed when chlorine gains one electron.
  2. Chlorine is naturally in a gas state. When first discovered in the 1680s, chlorine was presented as a gas. Chloride, being an ion, mostly occurs in mineral supplements.
  3. Chlorine gas is yellow-green coloured. Since ions are not coloured, chloride is colourless ions in aqueous solutions.
  4. Since chloride is formed by gaining one electron, the number of electrons is different in the two of them. Chlorine has 17 electrons and protons. Since chloride gains one electron, they have 18 electrons but 17 protons. This makes them highly unstable and reactive.
  5. In elemental form, chlorine does not have inert configuration i.e., electronic configuration of the nearest inert element. Chloride having one extra electron has achieved inert configuration. Chloride has the configuration of the element, Argon.
  6. Since chlorine has not achieved inert gas configuration, they are highly electronegative. They are the third highest element in the electronegative series of elements. But chloride is least electronegative or not electronegative at all.


Chlorine and chloride are different from one another. Even though chloride is derived from chlorine, they cannot be compared for similarities or used in place of the other. Therefore it is important to know the difference between the two.

Chlorine is the 17th element of the periodic table with atomic mass 35.5. Since they are highly electronegative, for achieving inert configuration, they are used as a bleaching agent. chlorine is also considered to be a good oxidizing agent.

Chloride is the ion formed when chlorine gains an electron. So it is an anion which is highly unstable and reactive. Chloride is found in salt as sodium chloride. But otherwise, it is commercially used in laboratories to make other salts.

The main feature that distinguishes between chlorine and chloride is that chlorine has an equal number of protons and electrons, that accounts for their stability. But chloride has one extra electron when compared to the number of protons. This is why they are highly reactive.


  1. Spatial patterns of organic chlorine and chloride in Swedish forest soil – ScienceDirect
  2. Chloride and chlorine isotopes (36Cl and δ37Cl) as tracers of solute migration in a thick, clay‐rich aquitard system (wiley.com)