An ionic bond involves transfer of electrons from less electronegative to more electronegative atom and consequent formation of ions (Mascetta, 2003, p. 57). Ions have different properties than their original atoms, and are arranged in a crystalline lattice rather than forming individual molecules in liquid or solid phase. Conversely, covalent and hydrogen bonds are formed by sharing of valence electrons of outer energy shells (Mascetta, 2003, p. 58). Hydrogen bonding is a type of dipole-dipole attraction. High positive charge of hydrogen atom attracts electron pairs of neighboring electronegative atom resulting in dipole formation. Ionic bonds are strongest out of the three and have smallest interatomic distance. Ionic bonded compounds have higher boiling and melting points than hydrogen bonds, which in turn, have higher heats of vaporization and higher boiling and melting points than non-polar covalent bonded molecules (Mascetta, 2003, p. 57-62). Ionic molecules conduct electricity unlike covalent bonded molecules. Electronegativity difference between elements is highest for ionic bonds, followed by hydrogen and then covalent bonds. (Words 153)
Single, Double and Triple Bonds
Sharing of one pair of electrons between two atoms produces a single bond, two pairs of electrons a double bond and three electron pairs a triple bond (Mascetta, 2003, p. 62). Double and triple bonds result from four and six bonding electrons respectively, between two atoms. Triple bonds have highest electron density and greatest attractive force between nuclei and shared electrons, followed by double and then single bonds (Mascetta, 2003, p. 62). Triple bonds have shorter interatomic distances and higher bond strengths than double bonds, which in turn are stronger and shorter than single bonds. Bond order is three for triple bonds, two for double bonds and one for single bonds (Mascetta, 2003, p. 62). A single bond includes a sigma bond with electrons along the internuclear axis. Double bond consists of one sigma and one pi bond while a triple bond includes one sigma and two pi bonds. Pi bond electron orbitals overlap in planes perpendicular to sigma bond and to each other. (Words 152)
Ionic and Covalent Compounds
Sodium chloride (NaCl) and Lithium fluoride (LiF) are ionic, and methane (CH4) and hydrogen chloride (HCl) are covalent compounds. The same can be determined in two ways. Firstly, generally compounds between metal and non-metal, such as Li and F or Na and Cl are ionic while compounds between non-metals, such as C and H, or H and Cl are covalent (Bettelheim et al., 2009). Alternatively, electronegativity difference (EN) can facilitate determination of ionic or covalent character. For, NaCl and LiF, EN1.9 implying they are ionic while EN1.9 for HCl and CH4 highlighting their covalent nature (Bettelheim et al., 2009). (Words 91)
Single, Double and Triple Bonds
Sharing of one pair of electrons between two atoms produces a single bond, two pairs of electrons a double bond and three electron pairs a triple bond (Mascetta, 2003, p. 62). Double and triple bonds result from four and six bonding electrons respectively, between two atoms. Triple bonds have highest electron density and greatest attractive force between nuclei and shared electrons, followed by double and then single bonds (Mascetta, 2003, p. 62). Triple bonds have shorter interatomic distances and higher bond strengths than double bonds, which in turn are stronger and shorter than single bonds. Bond order is three for triple bonds, two for double bonds and one for single bonds (Mascetta, 2003, p. 62). A single bond includes a sigma bond with electrons along the internuclear axis. Double bond consists of one sigma and one pi bond while a triple bond includes one sigma and two pi bonds. Pi bond electron orbitals overlap in planes perpendicular to sigma bond and to each other. (Words 152)
Ionic and Covalent Compounds
Sodium chloride (NaCl) and Lithium fluoride (LiF) are ionic, and methane (CH4) and hydrogen chloride (HCl) are covalent compounds. The same can be determined in two ways. Firstly, generally compounds between metal and non-metal, such as Li and F or Na and Cl are ionic while compounds between non-metals, such as C and H, or H and Cl are covalent (Bettelheim et al., 2009). Alternatively, electronegativity difference (EN) can facilitate determination of ionic or covalent character. For, NaCl and LiF, EN1.9 implying they are ionic while EN1.9 for HCl and CH4 highlighting their covalent nature (Bettelheim et al., 2009). (Words 91)
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