Bonding Test

Electronegativity

Ability of an atom to attract electrons in a bond towards itself (atoms with greater electronegativity will take valence of lower electronegativity)

Octet Rule

Atoms want 8 valence elections (outer most electrons) to become stable (like the noble gas)

Large difference in electronegativity

Creates an ionic bond (one winning, one losing)

Small difference in electronegativity

Creates a covalent bond (a tie or slightly uneven)

Ionic compounds

Ionic bonds, formula unit, one metal and one nonmetal, very high difference in electronegativity

Ionic bonds

Electrons transferred from one element to another because of electrostatic attraction between ions (like magnets)

Molecular compounds

Covalent bonds, molecules, two or more nonmetals, polar or nonpolar

Covalent bonds

Electrons are shared between elements because the element’s electron clouds overlap on the outer orbitals; both electrons are strongly attracted to each other’s valence electrons

Metallic compounds

Metallic bonds, alloy, same metallic element, very low difference in electronegativity

Metallic bonds

Creates a “sea of electrons” that are not bound to one specific atom

Formula unit

Simplest ration of cations to anions

Molecules

Smallest unit of a molecular compound

Alloy

A mixture of metals

Electronegativity increases

Up and to the right

If elements form a bond, the electron cloud will move towards the more ___ atom

Electronegative

Bonded elements

Less energy state than when elements are separate

Atoms with lower energy

More stable

Energy is released when

Bonds are formed

Ionic bonds characteristics

Crystal lattice, hard and brittle, shatter when hit

Ionic bonds characteristics in water

Soluble (dissolve)

Melting/boiling point of ionic bonds

High melting/boiling point

Covalent bonds characteristics

Strong bonds, soft when hit because bonds don’t break, not conductive

Covalent bonds characteristics in water

Sometimes soluble (dissove)

Conductivity of ionic bonds

Conductive in liquid state and dissolved in water, not as a solid because ionic compounds are held in a fixed state and cannot move

Melting/boiling points of covalent bonds

Low melting/boiling point

Metallic bond characteristics

Strong, malleability, ductility, opacity, luster, deforms when hit

Melting/boiling points of a metallic bond

High melting/boiling point

Conductivity of metallic bond

Conductive

Metallic bond characteristics in water

Not soluble

Delocalized electron

An electron in an atom, ion, or molecule that is not connected to a single atom or covalent bond

Delocalized electrons give what properties to metals

Malleability, ductility, heat, electrical conductors, luster

Bonds store …

Energy

Bond energy

A direct measure of bond length; the shorter the bond length, the higher the bond energy

When a bond is broken what is released

It releases energy in the form of heat or light

One atom

Mono-

Two atoms

Di-

Three atoms

Tri-

Four atoms

Tetra-

Five atoms

Penta-

Six atoms

Hexa-

Seven atoms

Hepta-

Eight atoms

Octa-

Nine atoms

Nona-

Ten atoms

Deca-

Exceptions to Octet Rule

Boron, beryllium, hydrogen, helium, phosphorus, sulfur

Ionic compounds Lewis dot structure

Shows a clear transfer of electrons from a cation to an anion (formula unit)

Covalent compounds Lewis dot structure

Shows how the electrons are being shared to complete the octets of each atom in the molecule

Boron

Only requires 6 valence electrons

Beryllium

Only requires 4 valence electrons

Hydrogen and Helium

Never has more than 2 valence electrons

Boron, beryllium, hydrogen, helium

Too small to hold a full octet

Phosphorus, sulfur

Large enough to have empty d-orbitals that can be used to hold up to 12 valence electrons; “expanded octet”

Phosphorus

Can have up to 10 valence electrons

Sulfur

Can have up to 12 total valence electrons

Covalent bonding happens in

Two “areas” between two atoms

Sigma bond

Bond directly between the two atom’s nuclei; allows for flexibility in the bond so atoms can bend and stretch

Sigma bond is the

The first type of bond that forms

Pi bond

Above/below or left/right of the two atom’s nuclei; does not allow for stretching and bending

Sigma bond is a (what type of bond)

Single bond; long bond with less stored energy

Pi bond is a (what type of bond)

Double or triple bond; short bond with higher stored energy

VSEPR

Valence Shell Electron Pair Repulsion

VSEPR shows

The 3-D shape of an atom

VSEPR uses

Number of elements bonded to the center atom and number of non-bonding electrons (lone pairs) attached to central atoms

VSEPR model states

1. Lone pairs of electrons take up space around the central atom
2. Because lone pairs are pulled closer to the central atom and are not shared, they will take up more space around the central atom than a bonding pair of electrons

Linear

0 bonded or 2 atoms lone pairs to central atom and 0 lone pairs on central atom

Linear bond angle

180

Bent

2 bonded atoms to central atom and 2 or 1 lone pairs on central atom

Bent bond angle

<

Trigonal Planar

3 bonded atoms to central atom and 0 lone pairs on central atom

Trigonal Planar bond angle

120

Tetrahedral

4 bonded atoms to central atom and 0 lone pairs on central atom

Tetrahedral bond angle

109\.5

Pyramidal

3 bonded atoms to central atom and 1 lone pairs on central atom

Pyramidal bond angle

107\.3

Trigonal bipyramidal

5 bonded atoms to central atom and 0 lone pairs on central atom

Trigonal bipyramidal bond angle

120 “around equator”, 90 vertically

Octahedral

8 bonded atoms to central atom and 0 lone pairs on central atom

Octahedral bond angle

90

Nonpolar bonds

Equal sharing between two identical atoms (usually in gases); values are the same

Polar bonds

Unequal sharing between two different atoms; values are differnt

Electronegativity predicts

How strongly each atom will pull the electrons toward it’s nucleus

Greek letter Delta shows

Partial charge because electrons are pulled closer to one atom

Scale to determine polarity

Pauling Scale

Lone pair on central atom (polar or not)

Atom is polar

Different atoms around the central atom (polar or not)

Atom is polar

\-ide turns in to what (acid)

\-ic

What is in an acid

hydrogen + nonmetal or hydrogen + polyatomic ion

Binary acids

Only contain 2 different elements (hydrogen + monatomic ion)

\-ate turns into what

\-ic

\-ite turns into what

\-ous

Ternary acid

Contains a polyatomic ion

Cation

A positive ion

Anion

A negative ion

Ion

An atom or a group of atoms that has a net electric charge by gaining or losing one or more electrons

Polyatomic Ion

Ion that contains more than one atom

Monoatomic Ion

Ion with one atom; “simple ion

Multi-Valent Ion

The positive ion has more than one possible charge (roman numerals)

Valence electrons

Outer most electronsOutermost

Luster

The state or quality of shining by reflecting light; describes how mineral reflects light

Malleability

Ability to be flattened (flat piece of metal)