Chemical bonds Inorgchem lecture Flashcards
Consist of a single nucleus with a positive charge surrounded by a cloud of negatively charged electrons
Atom
Total energy of the system is lowered, atoms bond together to form
Molecule
Consist of an aggregation of atoms held together by valence forces
Molecule
Group of 2 or more atoms that form the smallest identifiable unit
Molecule
Contain 2 atoms that are chemically bonded
Diatomic molecules
2 identical atoms that are chemically bonded
Ex: O2
Homonuclear
2 different atoms chemically bonded together
Ex: CO
Heteronuclear
Molecules containing more than 2 atoms
CO2
Polyatomic molecules
A distinct substance formed by chemical union of two or more elements in definite proportion by weight
Chemical compound
Represents the number of atoms
Subscripts
Identical atoms bonding together with identical proportions and differ only in arrangements
Ex: CH3CH2OH
(CH3OCH3)
Isomers
Assemblies of atoms that have a net electrical charge
Ions
Ions that contain FEWER electrons than protons, have a net positive charge
Cations
Ions that contain MORE electrons than protons have a net negative charge
Anions
Contains both cations and anions in a ratio that results in no net electrical charge
Ionic compounds
Electrons are shared between bonded atoms and are simultaneously attracted to more than one nucleus
Covalent compounds
Contain cations and anions rather than discrete neutral molecules
Ionic compounds
Held together by attractive electrostatic interactions between cations and anions
Ionic compounds
Conatins both cations and anions that results in zero electrical charge
Ionic compound
The particles repel each other
Positive electrostatic energy
Particles are attracted to each other
Negative electrostatic energy
Name of the element followed by the word ion
Monoatomic cation
Ions positive charge is indicated by a roman numeral in parenthesis followed by the word ion
Stock system
Iron (II) ion
Iron (III) ion
Stock system
Uses 2 suffixes (-ic and -ous) that are appended to the stem of the element name
Common syatem
Ferrous ion
Ferric ion
Common system
Represents the greater of the 2 cation charges
-ic suffix
Represents the lower one
-ous suffix
Forms when the bonded atoms have lower total energy that that of widely separated atoms
Covalent bonds
3 types of covalent bonds
1- single
2- double
3- tripple bonds
Share 2 electrons
Single bond
Share 4 electrons
Double bonds
Share 6 electrons
Tripple bonds
Are formed when the atoms adopt specific positions relative to one another so as to maximize the bond strength
Bonds
Held together by shared electron pairs
Molecules
Has definite, fairly rigid structure or spatial distribution of its atoms
Molecules
A very simplified representation of the valence shell electrons in a molecule
Lewis Structure
Used to show how the electrons are arranged around insividual atoms in a molecule
Lewis Structure
Also known as Lewis dot diagrams
Lewis Structure
Atoms tend to bond in such a way that they have 8 electrons in their valence shell
Octet Rule
Substances that react during chemical reaction
Reactants
Substances formed during chemical reaction
Products
Two or more compounds combine to form one compound
Combination reaction
A complex molecule breaks down to make simpler ones
Decomposition reaction
Oxygen combines with a compound to form carbon dioxide and water, exothermic reactions, gives off heat
Combustion reaction
An acid and base react with each other, product is salt and water
Neutralization reaction
One element takes place with another element in the compound
Displacement reaction
Double displacement
Exchange
Metathesis reaction
Double replacement reaction
Two aqueous ionic compounds form a new ionic compound that is not soluble in water
Precipitation reaction
Involves a transfer of electrons between two species
Oxidation-reduction
Redox
A reaction that forms a complex
Complexation reaction
Concerned with valence which determines how atoms combine in definite ratios and how this is related to the bond directions and bond lengths
Structural chemistry
