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Chemical Bonding. Atoms that interact to form compounds are said to be chemically bonded . Whether atoms interact depends almost entirely on the arrangement of their outer energy level ( valence ) electrons. Only s and p sublevel electrons are thought of as valence
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Chemical Bonding
Atoms that interact to form compounds are said to be chemically bonded.
Whether atoms interact depends almost entirely on the arrangement of their outer energy level (valence) electrons.
Only s and p sublevel electrons are thought of as valence electrons.
The maximum number of electrons, total, in the s and p sublevels is __
The maximum number of electrons, total, in the s and p sublevels is 8.
Electrons in the d and f sublevels are NEVER in the outer energy level of an atom.
Ionic Bonds Electrons are transferred between atoms.
Ionic Bonds One atom gains electrons while another atom loses electrons.
Ionic Bonds When this happens, the charges within each atom are no longer balanced...
Ionic Bonds the atoms have become ions - one with a positive charge, the other negative.
Ionic Bonds The force of attraction between these opposite charges hold the ions together in an ionic bond.
Ionization - the process of removing an electron from an atom to form an ion.
Ionization energy - the energy needed to remove an electron from an atom.
Electron affinity - the tendency of an atom to attract electrons.
Electron affinity determines the type of bond formed.
Metals generally have a low electron affinity.
Nonmetals generally have a high electron affinity.
Covalent Bonds Electrons are shared between atoms.
Covalent Bonds Atoms with similar electron affinities usually form covalent bonds.
Covalent Bonds Both atoms have an equal attraction for the electrons being shared.
Covalent Bonds The force of attraction between the nuclei and the shared electrons holds the atoms together in a covalent bond.
Ionic or Covalent Chemical bonds are almost never totally ionic or totally covalent.
Ionic or Covalent Bond types are often expressed as a percentage of each type of bond.
CO and CO2 The closer two atoms are on the table, the more covalent their bond.
The farther apart two atoms are on the table, the more ionic their bond. NaCl
Ionic or Covalent 100% Covalent F2 100% Ionic FrF ZnS 50% Each
Metallic Bonds The electrons in metals can be thought of as being property of all the atoms.
Metallic Bonds The positive nuclei are surrounded by a "sea" of electrons.
Metallic Bonds These loosely-held electrons are responsible for metals being good conductors of electricity.
Hydrogen Bonds A special type of bond between a hydrogen atom in a covalent molecule...
Hydrogen Bonds and an unshared electron in a nearby molecule.
Hydrogen Bonds Since a hydrogen atom is so small, it can get very close to other atoms -
Hydrogen Bonds causing electrons in those atoms to be attracted to it.
This is especially important with small, polar molecules like water.
It makes water a VERY GOOD solvent - especially with other polar substances.
Hydrogen bonding is responsible for water's very high specific heat capacity...
the ability to absorb large amounts of heat with little change in temperature...
and its relatively high boiling point.
Diatomic Molecules two atoms of the same element covalently bonded together.
Diatomic Molecules Seven elements exist in nature ONLY as diatomic molecules.
Diatomic Molecules Know the seven diatomic molecules!!
Diatomic Molecules Hydrogen - H2 Nitrogen - N2 Oxygen - O2 Fluorine - F2
Diatomic Molecules Chlorine - Cl2 Bromine - Br2 Iodine - I2
There are 6 here in the shape of a 7
Polyatomic Ion A group of covalently bonded atoms that has an overall charge.
Polyatomic Ion This group of atoms acts like a single ion when combining to form compounds.
