Chlorine is a chemical compound with the chemical formula Cl2. it is considered as a second lightest halogen. At room temperature, it exists as a pale yellowish-green gas. Many students may have a doubt regarding whether Cl2 is polar or not. In this article, we will discuss it and will also cover its properties and applications.
So, Is Cl2 Polar or Nonpolar? Cl2 (Chlorine) is nonpolar in nature because of its linear symmetrical shape and it consists of two chlorine atoms having equal electronegativity. As a result, both atoms have equal charge distribution on them, and the molecule results in zero dipole moment that makes the chlorine molecule nonpolar.
Chlorine is a highly reactive element and exists in the gaseous state at room temperature. It has its texture as greenish-yellow.
This compound is a strong oxidizing agent and has the highest electron affinity among other elements.
In the periodic table, the Chlorine element is placed at the grid in period 3 and group 17.
As it is highly reactive, it is present in the earth’s crust in the form of ionic chloride compounds. After fluorine, Chlorine is the second most abundant halogen present in nature.
Commercially, chlorine is extracted from the brine by the electrolysis process. It was first synthesized in the year 1630 but was not declared as an important element.
If we talk about the chemical composition of the chlorine molecule, it consists of two atoms of chlorine attached by a covalent bond.
Its molecular mass is calculated as
Mol. mass of Cl2 = 2 * 35.45 (at mass of Cl) = 70.906 g/mol.
The geometry of the chlorine gas molecule is linear as it is a diatomic molecule. The diatomic molecules can only be bonded linearly.
Both atoms have equal electronegative value. Therefore, both atoms have an equal proportion of bonded electrons.
The electronegativity of the chlorine atom is 3.16.
Due to equal charge distribution on both atoms, there exists no polarity across the molecule.
Below is the image of the molecular structure (linear) of the Chlorine molecule.
Polar and Nonpolar Molecules?
The molecules are held by interatomic forces like covalent, ionic, hydrogen bond, and metallic bond. Out of these, covalent and ionic bonds are the strongest.
The covalent bonds can be polar and nonpolar that depends upon various factors like electronegativity, geometrical shape, and dipole moment of the entire molecule.
Polar Molecules: The molecules that have some magnitude of net dipole moment (non zero) are known as a polar molecule. These molecules have unequal distribution of charges on its atoms.
The covalent bond formed between two atoms is said to be polar if both atoms share a different proportion of charge. Examples of such molecules are H2O, NH3. You can check out the reason for the polarity of NH3.
There exist two poles in a molecule ie; positive and negative.
Nonpolar Molecules: These are the molecules that have zero dipole moment. The atoms in such molecules have an equal distribution of charge.
The atoms combine covalently to form a nonpolar molecule if the atoms share an equal proportion of charge. There exist no two poles in such a molecule.
Examples of such molecules are CCl4, Br2. You can check out the reason for the non-polarity of Br2.
Why is Cl2 a Nonpolar Molecule?
The chlorine gas molecule consists of two chlorine atoms. Both atoms have equal electronegativity ie; both have equal influence on the bonded pair of electrons.
Electronegativity is the term that depicts the strength of an atom to attract the bonded pair of electrons towards it.
The chlorine molecule is a diatomic molecule and therefore linearly connected.
As a result, Both Cl atoms share the same amount of charge due to which no polarity rises across it.
And its dipole moment also turns out to be zero.
for better understanding, check out the video.
Factors that affect the polarity of a molecule
Electronegativity: The term electronegativity is the most important parameter to check whether a molecule is polar or not.
If two atoms forming a covalent bond differ in their electronegativity, the bond formed tends to be polar in nature.
Due to the difference between the electronegativity of both atoms, they have an unequal share of the charge.
Dipole moment: The dipole of a molecule is the measure of its polarity. The polarity of a molecule is directly proportional to its dipole moment.
The dipole moment of a molecule is the product of charges and distance between them. It is a vector quantity ie; it has magnitude as well as direction.
D = Q * R
Geometrical Shape: The shape of a molecule also decides the polar or nonpolar nature of a molecule.
The molecules that are symmetrical in shape are nonpolar in nature whereas the molecules that are asymmetric are polar.
Note: It is necessary to keep in mind that a nonpolar molecule can have polar bonds within it but due to the symmetrical structure of the molecule, the polarity of those bonds gets canceled with each other.
Properties of Cl2
- Chlorine gas exists as a pale yellowish-green gas at room temperature.
- It has a suffocating smell.
- It is a highly reactive gas.
- The molecular mass of Cl2 is 35.453 g.mol -1.
- At the temperature of 20 °C, the density of this gas is 3.21*10 -3 g.cm -3. Ie; two and one-half times as heavy as air
- It is easily soluble in water. Therefore mixed in water for the purpose of chlorination.
- The melting point of chlorine is -101 °C and its boiling point is -34.6 °C.
- The standard potential of Chlorine is – 1.36 V.
- Its first ionization value is 1255.7 kJ.mol -1.
Uses of Cl2
- It is majorly used for treating drinking water by the process known as chlorination. Local authorities add the required amount of chlorine to disinfect the water from bacterial impurities.
- It is also used in industries for the manufacturing of dyes, paper, and paints.
- It is also used in the health care industries fr manufacturing of medicine.
- It is used to prepare antiseptics.
- It is also added to the swimming pool for disinfecting the pool water.
The chlorine molecule is a diatomic molecule consisting of two chlorine atoms. Both atoms have equal electronegativity. It means both share an equal proportion of charge.
As a result, the molecule formed by two chlorine atoms is nonpolar.
So guys, if you have any questions regarding the non-polarity of Cl2. Ask them in the comment section. I will surely reach out to you as soon as possible.