A polar covalent bond is formed by the sharing of electrons due to the electronegativity difference between the atoms. Let us discuss the examples of polar covalent bonds.
The examples of polar covalent bonds are listed below-
- পানি
- হাইড্রোজেন ত্ত নাইট্রোজেন গ্যাসের মিলনে গ্যাসীয়
- নাইট্রোসিল ক্লোরাইড
- নাইট্রিক এসিড
- কার্বন মনোক্সাইড
- ফসফরাস পেন্টক্সাইড
- কার্বন টেট্রাক্লোরাইড
- সালফার ডাই অক্সাইড
- হাইড্রোজেন সালফাইড
- ইথানল
- সালফেট আয়ন
- কার্বন - ডাই - অক্সাইড
- হাইড্রোজেন পারঅক্সাইড
- হাইড্রোজেন সায়ানাইড
- অ্যাসিটোন
পানি
পানি is a significant example of a polar covalent bond because the বৈদ্যুতিনগতিশীলতা difference between hydrogen atom and oxygen atom is considerably high. Therefore, the bond pair electrons are shifted towards the oxygen side than the hydrogen side and oxygen becomes a polar molecule with a high dipole moment.
হাইড্রোজেন ত্ত নাইট্রোজেন গ্যাসের মিলনে গ্যাসীয়
Ammonia becomes a পোলার অণু because of the presence of the polar bond ie N-H bond. The electronegativity of nitrogen and hydrogen is 3.04 and 2.2 (on the Pauling scale). Therefore, the electron cloud is shifted towards the nitrogen atom and ammonia becomes a polar molecule with a ডিপোল মুহূর্ত of 1.48 D.
Nitrosyl Chloride
Nitrosyl chloride is also an example of a polar covalent bonding because there is a significant difference in electronegativity between nitrogen, oxygen, and chlorine. Therefore, N=O and N=Cl bonds are significantly polar and the overall NOCl molecule shows a permanent dipole moment.
নাইট্রিক এসিড
নাইট্রিক এসিড is regarded as a polar covalent molecule because the covalent bonding between nitrogen and oxygen is polar due to the electronegativity difference between them. Being higher electronegative, oxygen pulls the N-O bond pair electrons towards itself and nitric acid becomes a polar molecule.
কার্বন মনোক্সাইড
Carbon monoxide is also an example of a polar covalent bond because the electronegativity difference between oxygen and carbon is relatively high (3.44-2.55). Therefore, bond pair electrons cannot be shared equally between oxygen and carbon and they are shifted towards oxygen due to higher electronegativity.
ফসফরাস পেন্টক্সাইড
Phosphorus pentoxide is listed as an example of a polar covalent bond because there is a significant difference in electronegativity between phosphorus and oxygen. Therefore, the electron pairs of P-O bonds are shifted towards oxygen because it is more electronegative than phosphorus.
কার্বন টেট্রাক্লোরাইড
Carbon tetrachloride is a non polar covalent molecule but all of the C-Cl are polar bonds. But due to the orientation of the four C-Cl bonds, bond moments are canceled by each other and the dipole moment becomes zero. C-Cl bonds show polarity because there is a difference in electronegativity between C and Cl.
সালফার ডাই অক্সাইড
সালফার ডাই অক্সাইড is a polar molecule and the S-O bonds present in it are significantly polar. This polarity arises due to the electronegativity difference between sulfur and oxygen. Therefore, the bond pair electrons are shifted towards oxygen than sulfur as oxygen is more electronegative than sulfur.
হাইড্রোজেন সালফাইড
Hydrogen sulfide possesses a V-shaped (angular) structure with two polar bonds ie S-H bonds and the bonding electrons of these two S-H bonds are shifted toward the sulfur atom. Therefore H2S has a permanent dipole moment of 0.95 D.
ইথানল
Ethanol is a polar molecule with polar bonds between C-O and O-H. Therefore, the electron pairs in both the C-O and O-H bonds are shifted toward the oxygen atom because it is more electronegative than C and H (the electronegativity of C, H, and O is 2.55, 2.2, and 3.44 respectively on the Pauling scale).
Sulfate Ion
In sulfate ion, two S=O and twp S-O bonds are present. All of these four bonds are polar because there is a difference in electronegativity between sulfur and oxygen. Therefore, the bonding electron pairs cannot be shared equally in those S=O or S=O bonds. They are slightly shifted toward the oxygen atoms.
কার্বন - ডাই - অক্সাইড
Like carbon tetrachloride, carbon dioxide is also a non polar molecule but with polar bonds. Due to the linear structure, CO2 possesses zero dipole moment. Two of the C=O bonds are polar because the electronegativity difference between carbon atom and oxygen atom is high and the bonding electrons are shifted toward oxygen.
হাইড্রোজেন পারঅক্সাইড
Hydrogen peroxide is also a polar molecule with two polar O-H bonds. This polarity arises due to the electronegativity difference between oxygen and hydrogen atoms. Therefore, the bonding electron pairs cannot be shared equally between them and the electron pairs are shifted toward oxygen.
হাইড্রোজেন সায়ানাইড
Hydrogen cyanide is an example of a polar covalent bond because carbon, oxygen, and hydrogen differ from each other in electronegativity. Therefore, the triple bond present in this molecule between carbon and nitrogen becomes polar and the bonding electrons are pulled by the N because of its higher electronegativity.
অ্যাসিটোন
Acetone is also an example of a polar covalent bond because there is a difference in electronegativity between carbon, hydrogen, and oxygen. The C=O bond is sufficiently polar because oxygen is more electronegative than carbon. Therefore, the bonding electron pairs of the C=O bond are pulled toward oxygen.
Polar Covalent Bond
A polar covalent bond is a covalent linkage that contains a considerable difference in electronegativity between the bond-forming atoms. A covalent bond is formed between two atoms by sharing of electron pairs. The sharing of electron pairs depends upon the electronegativity difference between the atoms.
Properties of Polar Covalent Bond
The properties of polar covalent bonds are written below-
- Bonds must be formed due to the mutual sharing of electron pairs.
- Polar covalent bonds must have a difference in electronegativity.
- The atoms that participate in the formation of a polar covalent bond must be different.
- It is not necessary that non polar molecules cannot have polar bonds.
When is a polar covalent bond formed?
A polar covalent bond is formed in the following cases-
- When the difference in electronegativity occurs between two atoms.
- When electron pairs are shared between those atoms, not the complete transfer of electron pairs takes place.
How to determine a polar covalent bond?
The polarity of a covalent bond is determined by the difference in the electronegativities of the two atoms participating in bond formation. The greater the difference in electronegativity, the greater the imbalance of electron pairs sharing in the bond.
How are electrons shared in a polar covalent bond?
Sharing of electrons in a polar covalent bond depends upon the relative electronegativities of the two atoms in the bond. The bonding electron pairs are shifted toward the more electronegative atom. The more displacement of the electrons, the bond will be more polar.
Polar Covalent Bond Boiling Point
Polar molecules always have high boiling as well as melting point than non polar molecules because they have strong attractive forces within themselves or other molecules.
Polar Covalent Bond Conductivity
The molecules with polar covalent bond conduct electricity. The conductivity arises due to the mobility of ions in the solution.
Polar Covalent Bond Solubility
Molecules with polar covalent bonds dissolve in any polar solvent like-
- পানি
- ক্লর্যাফর্ম প্রয়োগ করা
- হাইড্রোজেন ত্ত নাইট্রোজেন গ্যাসের মিলনে গ্যাসীয়
- অ্যাসিটোন
- DMF
- ডিএমএসও
- এসিটোনাইট্রাইল
- ইথানল
Polar Covalent Bond Strong or Weak
Polar covalent bonds are very strong bonds because the bonds are formed due to the mutual sharing of electron pairs between the atoms. The strength of the bond depends upon the relative electronegativity difference between the atoms.
Are polar covalent bonds hydrophobic?
Polar covalent bonds are not hydrophobic, rather they are hydrophilic. Polar bonds attract water like polar solvents. Non polar bonds are generally hydrophobic in nature and they are repelled by polar solvents.
Polar Covalent Bond Examples in Real Life
The following examples of polar covalent bonds are observed in real life-
- পানি
- হাইড্রোজেন ত্ত নাইট্রোজেন গ্যাসের মিলনে গ্যাসীয়
- ইথানল
- হাইড্রোজেন ফ্লোরাইড
- কার্বন - ডাই - অক্সাইড
- নাইট্রিক এসিড
- ক্লর্যাফর্ম প্রয়োগ করা
Polar vs Nonpolar Covalent Bond Examples
| পোলার সমযোজী বন্ধন | Nonpolar covalent bonds |
|---|---|
| পানি | আলকাতরা হইতে উত্পন্ন বর্ণহীন তরল পদার্র্থবিশেষ |
| হাইড্রোজেন ত্ত নাইট্রোজেন গ্যাসের মিলনে গ্যাসীয় | মিথেন |
| ফসফরাস pentachloride | অক্সিজেন |
| ওজোন গ্যাস | Dihydrogen gas |
| থার | হীরা |
| কার্বক্সিলিক অ্যাসিড | উজ্জ্বল শিখাযুক্ত বর্ণহীন গ্যাসবিশেষ |
| প্রোপানল | কৃষ্ণসীস নামক ধাতু |
Polar Covalent Bond vs Ionic Bonds
| পোলার সমযোজী বন্ধন | আয়নিক বন্ড |
|---|---|
| A Polar covalent bond is formed due to the sharing of electron pairs between two atoms. | An ionic bond is formed due to the complete transfer of electron pairs from one atom to another atom. |
| The bond formation atoms must be a combination of two nonmetal atoms. | One atom must be metal between the two atoms involved in the formation of an ionic bond. |
| The difference with a polar covalent bond is 0.5 to 1.7. | If the difference in the electronegativity between the two elements is greater than 1.7 then the bond is ionic. |
Polar Covalent Bond vs Hydrogen Bond
| পোলার সমযোজী বন্ধন | হাইড্রোজেন বন্ধন |
|---|---|
| Polar covalent bonds are chemical bond that are formed due to the sharing of electrons. | A hydrogen bond is formed between a highly electronegative atom and hydrogen from a different molecule attached to any electronegative element. |
| A polar covalent bonding can only be intramolecular | Hydrogen bonds can be intramolecular and intermolecular |
| The strength of a polar covalent bond is 100-1000 KJ/mol | The strength of a hydrogen bond is 5-50 KJ/mol |
উপসংহার
A nonpolar covalent molecule can have polar covalent bonds like carbon dioxide. Due to the mutual cancellation of the bond moment, the molecule has zero dipole moment.
