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19 Cards in this Set
- Front
- Back
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Chemical Bond
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bonds between atoms and/or ions
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Ionic Bond
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electrostatic bonds between ions of opposite charges
Tend to be metal cations bonded to nonmetal anions Ionization energy measures how easily an e- is relinqueshed Electron affinity measures how easily an e- is gained |
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Covalent Bond
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sharing electrons between two atoms
tend to be among nonmetals glucose: C₆H₁₂O₆ |
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Metallic Bonds
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bonds among metal atoms
electrons relatively free to move within the 3d structure |
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Lewis Symbol
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Element symbol plus a dot for each valence electron, two dots allowed top, bottom, and each side
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Octet Rule
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atoms tend to gain, lose, or share electrons until they are surrounded by 8 valence electrons
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Energetics of Ionic Bond Formation
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tend to be exothermic
Removing an e- from metal is endothermic, gaining an e- to a nonmetal is exothermic The above measurements assume the atoms are not interacting, lattice energy compensates for this |
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Lattice Energy
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energy required to completely separate a mole of a solid ionic compound into its gaseous ions
The process of formation is the inverse Larger positive value indicates stronger attraction for ions within compound causes high melt point, hard, brittle For a given arrangement of ions, the lattice energy increases as the charges on the ions increase and as their radii decrease |
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Transition Metal Ions
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lose valence shell s electrons first, than as many d electrons as are required to reach the charge of the ion
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Covalent Bond attractions
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attraction between nucleus of one and electrons of another must be strong enough to overcome the repulsion of nucleus:nucleus and e:e
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Lewis Structures
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Use atomic symbol with dots around it to represent valence electrons
Use a line to denote a pair of electrons shared by two atoms |
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Single/Double/Triple Bonds
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each denoted by a line, distance between bonded atoms varies indirectly with number of shared bonds
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Bond Length
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distance between the nuclei involved in a bond
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Bond Polarity
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describes how equally electrons are shared between atoms
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Nonpolar Covalent Bond
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only when e- are equally shared, e.g. diatomic molecule
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Polar Covalent Bond
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One atom exerts greater attraction than the othe
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Electronegativity
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The ability of an atom in a molecule to attract electrons to itself
related to ionization energy and electron affinity very negative electron affinity & high ionization energy yields high electronegativity |
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Electron Affinity vs Electronegativity
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Affinity measures energy released when an isolated atom gains an electron. Electronegativity measures the ability of an atom to retain its own electrons whilst attracting electrons from other atoms in compounds.
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Bond Polarity
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pure covalent<.5<polar covalent<2.1<ionic
the greater the difference in electronegativity, the more polar the bond |
