Chapter 7 Chemical Reactions

Chapter 7 – Chemical Reactions Name ______

A. Chemical Equations:

Examples: Solid Iron reacts with oxygen to form ironIIIoxide.

Words:

Symbols:

Aqueous Hydrogen peroxide decomposes to produce water and oxygen gas.

Words:

Symblos:

Methane burns to form energy carbon dioxide and water.

Words:

Symbols

*Skeleton equations –

Symbols: yield reversible reaction solid precipitate Liquid aqueous (in water solution) Gas gas as a product Heat catalyst B. Balancing Equations

Balanced equations have ______

Law of Conservation of Mass:

Rules for balancing equations: 1. Write the correct chemical formulas for the reactants and the products (must use ion chart and don’t forget HONClBrIF diatomic elements) 2. Write the reactants on the left and the products on the right using the “+” to separate compounds and the  to separate the reactants form the products. 3. Count the number of atoms of each element in the reactants and in the products ( NOTE: the same polyatomic appearing on both sies of the yiel arrow should be counted as 1) 4. Balance the number of atoms of each element using coefficients. DO NOT CHANGE THE SUBSCRIPTS (coefficient- the LARGE whole number in front of the chemical formula) **Balance elements appearing 3 or more places in the equation last. 5. Check each element to make sure the equation is blalanced. 6. Make sure all coefficients are in the lowest whole number ratio.

C. Examples:

C (s) + O2(g)  CO2(g)

To balance use coefficients. DO NOT CHANGE FORMULAS.

___ C (s) + ___ O2(g)  ___ CO(g)

___ AgNo3(aq) + ___ Cu(s)  ___ Cu(NO3)2 (aq) + ___ Ag (s)

___ Al(s) + ___ O2(g)  ___ Al2O3(s)

___ C2H6(s) + ___ O2(g)  ___ CO2 + ___ H2O

___ H3PO3  ___ H3PO4 + ___ PH3

Worksheet #2 and #3 Quiz on above material D. Types of Chemical Reactions 1. Combination Reactions -

EXAMPLE:

*2. Decomposition reactions -

EXAMPLE:

*3. Single Replacement Reactions -

EXAMPLE:

4. Double Replacement Reaction –

EXAMPLE:

5. Combustion Reaction (BURNING)

EXAMPLE: F. *SPECIAL REACTIONS ( x represents a metal)

-2 Decomposition of a CARBONATE ( CO3 )

Decomposition of an HYDROXIDE (OH-)

-1 Decomposition of a CHLORATE (ClO3 )

Single Replacement of a Group IA or IIA metal + water