The covalent bond is an interaction between atoms resulting in sharing of electrons and formation of a common electron pair situated between them. Polar or non-polar covalent bond is distinguished depending on whether the common electron pair is closer to one of the atoms or is equally distant from both of them. The number of shared pair of electrons defines the bond type: single, double, and triple. The non-metal elements usually form covalent bonds. The covalent bond is the most common type of bonding in the organic compounds.

• Formation of a covalent bond
• Polar and non-polar covalent bond
• Simulations
• Problems and tests

Formation of a covalent bond

http://207.10.97.102/chemzone/lessons/03bonding/mleebonding/covalent_bonds.htm Acovalent bond exists when two electrons are shared by two non-metallic atoms: animated example for Cl₂ molecule.

http://mychemistrypage.future.easyspace.com/General/bonding/covalent.htm Covalent bonding occurs between non-metal atoms.

http://wine1.sb.fsu.edu/chm1045/notes/Bonding/Covalent/Bond04.htm Representation of the covalent bond in Lewis structures.

http://stezlab1.unl.edu/Chem251/Review/Covalent_Bonding/lewis_structure_of_hno3.htm Representation of the covalent bond in Lewis structures - HNO₃ molecule.

http://www.nyu.edu/classes/tuckerman/honors.chem/lectures/lecture_6/node1.html Electron density plots of an H₂ molecule at four different separations between the atoms.

http://www.learn.co.za/content/grade11/Science/chem_bonding/chem_bond/Unit2/ Lewis and Couper notations for H₂O, CH₄, NH₃, CO₂ molecules.

http://www.s-cool.co.uk/ Examples for compounds with covalent bonds.

http://www.chem.ufl.edu/~chm2040/Notes/Chapter_11/covalent.html Examples for covalent bonds lengths.

http://www.usm.maine.edu/~newton/Chy251_253/Lectures/Shapes/ShapesFS.html Examples for molecular shapes. [Back to top]

Polar and non-polar covalent bond

http://web.jjay.cuny.edu/~acarpi/NSC/5-bonds.htm Animated illustration of the non-polar H₂ molecule, in which two hydrogen atoms equally share electrons to form a covalent bond. When one atom has a greater affinity for electrons in a molecule, the shared electrons will spend more time around that atom and the bond formed will be a polar covalent bond - H₂O; molecule.

http://www.chem.ox.ac.uk/vrchemistry/electronsandbonds/bondsperatom1.htm The polarity of the covalent bond depends on the difference in electronegativities between two bonded atoms.

http://www.usm.maine.edu/~newton/Chy251_253/Lectures/Polarity/PolarityFS.html Symmetrical and unsymmetrical distribution of electronic density.

http://www.citycollegiate.com/bondIXc.htm Example for a polar covalent bond – HCl molecule.

http://www.csupomona.edu/~egoldstein/121/LDS-COVA.HTM Lewis representation for covalent compounds.

http://mdp2.phys.ucl.ac.uk/Talks/Ice/Ice.html Structure of water molecules in ice.

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Simulations

Formation of H₂ molecule

Formation of Cl₂ molecule

Rotation of Cl₂ molecule

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Problems and tests

http://lrc-srvr.mps.ohio-state.edu/under/chemed/qbank/quiz/bank6.htm   Covalent bond.

http://www.csupomona.edu/~egoldstein/121/test.htm Covalent bond.

http://www.chem.ox.ac.uk/vrchemistry/electronsandbonds/Questions1.htm   Covalent bond.

http://207.10.97.102/chemzone/lessons/03bonding/dogbonds.htm   Comparison of different bonds.

http://www.mynewschool.co.uk/revise4it-home.htm   Comparison of different bonds.

http://www.odonel.k12.nf.ca/science/tut-bond/problems.htm Nature of the chemical bond.

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