*glitterfy1121750T427D30[1].gifBy Kayla H. and Sarah A.Table of ContentsOther FactsHow Covalent Bonds Form*Electron Sharing*How Many Bonds?*Double Bonds and Triple BondsMolecular Compounds*Low Melting Points and Boiling Points*Poor ConducivityUnequal Sharing of Electrons*Polar Bonds and Nonpolar Bonds*Polar Bonds in Molecules *Attractions Between MoleculesOther Facts*In most covalent bonds, the shared pair of electrons has at least one electron from each atom (See ).*In some special covalent bonds, both electrons in a pair come from the same atom (See ). * * *What is a covalent bond?"A covalent bond is a chemical bond formed when two atoms share electrons." (J., Miaoulis, Cyr, V., L., Coolidge-Stoltz, Lisowski, Garbuny, Wysession, Brooks, M., V., Griffith, Linda, Carl, G., and Hall 31-35) * * *How Covalent Bonds FormElectron SharingWhen two or more atoms share electrons, a covalent bond is formed. The noble gases (including Hydrogen) along with other non-metals bond with other gases or non-metals by sharing electrons. Covalent bonding is only used by non-metals and gases while ionic bonding is used by metals and nonmetals. When sharing electrons between one another, each bonded element should contain 8 electrons so that the outer shell can be full. The attraction of each atom's nucleus in a pair of shared electrons is what holds the atoms in a covalent bond together. (J., Miaoulis, Cyr, V., L., Coolidge-Stoltz, Lisowski, Garbuny, Wysession, Brooks, M., V., Griffith, Linda, Carl, G., and Hall 31-35) * * *What is a molecule?"A molecule is a neutral group of atoms joined by covalent bonds" (J., Miaoulis, Cyr, V., L., Coolidge-Stoltz, Lisowski, Garbuny, Wysession, Brooks, M., V., Griffith, Linda, Carl, G., and Hall 31-35) * * *How Many Bonds? For a shell to be full, an atom needs a total of 8 electrons. However, Hydrogen only needs 2 electrons in its outer shell to be full. The number of bonds an atom can form depends on the number of electrons the atom needs in its outer shell to be full. For example, Oxygen has 6 electrons in its outer shell. It needs 2 more to be full and it can form 2 bonds. Hydrogen has 1 electron in its outer shell. It only needs 1 more to be full and it can form 1 bond. Oxygen could bond with 2 different Hydrogen atoms which would make each atom have a full shell. This is an example of covalent bonding. (J., Miaoulis, Cyr, V., L., Coolidge-Stoltz, Lisowski, Garbuny, Wysession, Brooks, M., V., Griffith, Linda, Carl, G., and Hall 31-35) Double Bonds and Triple BondsA double bond is when 2 pairs of electrons are shared by atoms. A triple bond is when 3 pairs of electrons are shared by atoms. Below are examples of double and triple bonds. (J., Miaoulis, Cyr, V., L., Coolidge-Stoltz, Lisowski, Garbuny, Wysession, Brooks, M., V., Griffith, Linda, Carl, G., and Hall 31-35)
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Molecular Compounds* * *What is a molecular compound?"A molecular compound is a compound that is composed of molecules." (J., Miaoulis, Cyr, V., L., Coolidge-Stoltz, Lisowski, Garbuny, Wysession, Brooks, M., V., Griffith, Linda, Carl, G., and Hall 31-35) * * *Low Melting Points and Boiling PointsMolecular compunds have lower melting and boiling points compared to ionic compounds. This is because the force holding the molecules together is weak. This means that less heat and a lower boiling point is needed because the weak force makes the molecules easily seperate. (J., Miaoulis, Cyr, V., L., Coolidge-Stoltz, Lisowski, Garbuny, Wysession, Brooks, M., V., Griffith, Linda, Carl, G., and Hall 31-35) Poor ConductivityMolecular compounds don't conduct electricity. This is because there aren't any charged particles that can move around. Rubber and plastic are examples of this. Both molecular compounds don't conduct electricity. Molecular compounds are also poor conductors when in liquid form. Examples of liquids that don't conduct when dissolved are pure water with sugar in it and alcohol. (J., Miaoulis, Cyr, V., L., Coolidge-Stoltz, Lisowski, Garbuny, Wysession, Brooks, M., V., Griffith, Linda, Carl, G., and Hall 31-35) Unequal Sharing of Electrons"Atoms of some elements pull more strongly on shared electrons than do atoms of other elements." (J., Miaoulis, Cyr, V., L., Coolidge-Stoltz, Lisowski, Garbuny, Wysession, Brooks, M., V., Griffith, Linda, Carl, G., and Hall 31-35) Polar Bonds and Nonpolar BondsThere are 2 things that can happen to an atom when the electrons are shared unequally: The atom with a strong pull will become slightly negative and the atom with a weak pull will become slightly positive. A polar bond is when electrons in a covalent bond are shared unequally. A nonpolar bond is when electrons in a covalent bond are shared equally. (J., Miaoulis, Cyr, V., L., Coolidge-Stoltz, Lisowski, Garbuny, Wysession, Brooks, M., V., Griffith, Linda, Carl, G., and Hall 31-35) Polar Bonds in MoleculesA molecule can be nonpolar and contain polar bonds. However, if a molecule has a polar covalent bond, it will be polar. When two atoms pull with equal strength in opposite directions, the attractions cancel eachother out resulting in a nonpolar bond. Molecules with polar covalent bonds are generally polar. (J., Miaoulis, Cyr, V., L., Coolidge-Stoltz, Lisowski, Garbuny, Wysession, Brooks, M., V., Griffith, Linda, Carl, G., and Hall 31-35) Attractions Between Molecules
Negatively charged molecules attract positively charged molecules. There is little attraction between nonpolar molecules. Polar and nonpolar compounds differ because they don't have molecules that attract eachother. Nonpolar molecules are attracted to and usually stay with other nonpolar molecules. Polar molecules are attracted to and usually stay with other polar molecules.
(J., Miaoulis, Cyr, V., L., Coolidge-Stoltz, Lisowski, Garbuny, Wysession, Brooks, M., V., Griffith, Linda, Carl, G., and Hall 31-35)
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In the cartoon, the boy represents Oxygen and the 2 girls represent Hydrogen. The toys represent electrons. When the boy makes 2 bonds and each girl makes 1 bond, the kids are all happy. This is like a covalent bond. 






Works Cited J., Michael, Ioannis Miaoulis, Martha Cyr, Janann V., Donald L., Elizabeth Coolidge-Stoltz, Marylin Lisowski, Carole Garbuny, Michael Wysession, Barbara Brooks, Jay M., David V., T. Griffith, Camille Linda, Andrew Carl, Russell G., and PearsonPrentice Hall. Prentice Hall science explorer. Boston,MA: Pearson Prentice Hall, 2009. 31-35. Print. See , Pauling. "Chemical Bonding." The Nature of the Chemical Bond. 3rd. Cascadilla Street Ithaca, NY : Cornell University Press, 1960. Print. "Covalent Bonds." ToonDoo. Web. 18 May 2011. http://www.toondoo.com/MyToondoo.toon."Covalent Bonding." Glogster. Web. 18 May 2011. http://watermelon56.glogster.com/covalent-bonding/."Covalent Bonding." Prentice Hall. Web. 17 May 2011. http://www.pearsonsuccessnet.com/snpapp/iText/BrowseITEXTServlet?eventType=openIEXT&ISBN=0-13-036747-8&ISBNUrl=%2FiText%2Fproducts%2F0-13-036747-8%2Findex.html&ITEXTOID=0-13-036747-8&EnrollmentOID=90E9503ED92D7C3AE040A00AAF0E43BF&DisplayTitle=Science+Explorer+Chemical+Interactions+%28L%29&TitleInFrame=Y&classPeriodOid=27f084b811ff4bdb98a6a41681fccc00&isbnUrlIsJavascript=false.