Chemistry #2

Oxidation Reaction

An oxidation reaction (oxidation-reduction, or “redox”

reaction) is any reaction where there is a transfer of electrons

between the chemicals (originally thought to be just the loss

or gain of oxygen)

The species (element or compound) that loses electrons is

oxidized, whereas the species that gains electrons is reduced

Word Equations

simplify and describe the

conversion of reactants to products without

the use of chemical symbols or formulas.

FACTORS AFFECTING REACTION

RATE

Concentration of reactants - Higher concentration = more particles = more

collisions

Temperature of reactants - molecules move faster = more collisions

Surface Area of reactants - more molecules available for collisions = more

collisions

Agitation - The more particles

are moved around

the higher the

chance of particles

colliding with each

other

Apply a catalyst -

Electrolysis - Electricity

causes bonds

to break in

molecules

which forces

molecules to

react or

separate

Chemical formulas

uses symbols

and numerals to represent the

composition of a pure substance

Each symbol in a chemical formula

represents an atom of an element

If there is more than one atom of

an element, a small number written

below the line follows the element

symbol

This subscript shows the number of

atoms

Ion (types)

The positive ion is

called a cation

Cats have paws, so

think ‘paws’itive

for the cation

The negative ion is

called an anion

Think ‘a negative’

ion

What are ions

A positively or negatively charged atom

Ionic compoinds

One or more metal ion(s) Examples: NaCl, MgO,Al2O3

combine with one or more

non-metal ion(s) to form

an extremely strong bond

where atoms transfer to

other electrons, due to the

opposite charges of the

ions

MOLECULAR

COMPOUNDS

Combination of two or

more non-metals where

the atoms share electrons,

due to the fact that they

are not in their ion forms

Examples: H2O, N2O3,

CO2

PROPERTIES OF IONIC

COMPOUNDS

Are a combination of positive and negative

ions

Have extremely strong bonds

Have high melting and boiling points

Are solids at room temperature

Conduct electricity

Forms ions in solution

Form distinct crystal shapes

Held together with ionic bonds

PROPERTIES OF MOLECULAR

COMPOUNDS

Are a combination of elements not in their

ion form

Have bonds that are relatively weak

Have relatively low melting and boiling

points

Can be solids, liquids, or gases at room

temperature

Are poor conductors of electricity

(insulators)

Rarely form crystals when in their solid

form

HOW ARE IONIC COMPOUNDS

NAMED?

The name includes both elements in the

compound, with the name of the metallic

element first

The non-metallic element is second, Its ending

is changed to -ide.

Subscripts indicate the ratio of ions in the

compound. For example, in CaCl2 the ratio of

calcium to chloride ions is 1:2.

HOW ARE MOLECULAR COMPOUNDS

NAMED?

Write the entire name of the first element

Change the ending on the name of the second element to

-ide.

Use a prefix to indicate the number of each type in the

formula: mono-for one, di-for two, tri-for three, tetra-for

four, penta-for five, hexa-for six, hepta-for seven, and

octa-for eight. (The prefix mono- is used only for the

second element.)

Rules for changing from the written name to the

chemical formula:

Write the symbols for the elements in the same

order as they appear in the name.

Use subscripts to indicate the numbers of each

type of atom.

DIATOMIC MOLECULES

Compounds made up of two atoms (often the same

two atoms)

All are gases at room temperature (if they are

homonuclear diatomic molecules)

Examples:

Hydrogen H2

- Chlorine Cl2

Nitrogen N2

- Bromine Br2

Oxygen O2

- Iodine I2

Flourine F2

Heteronuclear diatomic molecules consist of two

different elements (ex: NaCl)