Chemical Bonding

Physical Science - Middle School

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metal nonmetal Chemical Bonding © Copyright NewPath Learning. All Rights Reserved. 94-4838 Visit www.newpathlearning.com for Online Learning Resources. Chemical Bonds In 1916, Gilbert Newton Lewis, an American scientist, proposed that chemical bonds are formed due to the electron interaction between atoms. His work established the basis of what we know today about chemical bonding. Atoms combine with other atoms through chemical bonds, which result from the strong attractive forces that exist between the atoms. Atoms bond together to become more stable by having a full valence shell. Certain elements are more reactive than others and will be more likely to bond with other elements. There are three main types of chemical bonding: covalent bonding, ionic bonding and metallic bonding. Covalent Bonding The bond between two nonmetals is usually a covalent bond. By sharing electrons, two atoms can mutually complete their valence shells to become more stable. Ionic Bonding The bond between a metal and nonmetal atom is an ionic bond. In this example, to become stable, the metal sodium atom loses one electron in its outer shell, which is gained by the nonmetal chlorine atom, which also becomes stable with a full outer shell electron configuration. H Cl HCl shared electrons Cl- Na+ Cl Na + Cl- Na+ Cl Na + Metallic Bonding Metal atoms bond by forming a metallic bond. The valence electrons in a metallic substance continually move throughout the metal from one atom to another. The atoms that the electrons leave behind become positive ions. The interaction between such ions and valence electrons provides the bonding force that holds a metallic structure together. + + + + + + + + + + + + Al+ ion loose valence electrons loose valence electrons shared electrons
Chemical Bonding Pause and Review Describe and illustrate the three types of chemical bonding. © Copyright NewPath Learning. All Rights Reserved. 94-4838 Visit www.newpathlearning.com for Online Learning Resources. 1. Covalent Bonding ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ 2. Ionic Bonding ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ 3. Metallic Bonding ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________ ___________________________________