Chapter 7 (review for exam #2)

New compounds

-Potentially insoluble ones- are now possible specifically, that cation from one compound can now pair with the anion from the other compound to form new and potentially insoluble products

Describe the differences between a complete ionic and net ionic equation

A complete ionic equation shows the reactants and products as they are actually present in solution. The net ionic equation shows the species that actually change during the reaction. Spectator ions are shown in the complete ionic equation but are not shown in the net ionic equation

Decomposition reaction

A complex substance decomposes to form simpler substances

Redox equations are those in which

A substance reacts with elemental oxygen, a metal reacts with a nonmetal, more generally one substance transfers electrons to another substance

Combustion reacts

A substance reacts with oxygen, emitting heat and forming one or more oxygen containing compounds

Oxidation reduction reactions

A type of combustion reaction, in which electrons are transferred from one substance to another

Many evolution reactions are also

Acid base reactions

Two other equations that occur in solution are

Acid base reactions and gas evolution reactions

What are the properties of acids and bases?

An acid is a compound characterized by its sour fast its ability to dissolve some metals, and it's tendency to form H+ ions is solution. A base is a compound characterized by its bitter taste, it's slippery feel and its tendency to form OH- ions in solution

Molecular equation

An equation showing the complete neutral formulas for every compound in the reaction

Aq

Aqueous (water solution)

Combustion reactions

Are a type of redox reaction. They are important because most of our societies energy is derived from combustion reactions. Combustion reactions are characterized by the reaction of a substance with O2 to form one or more oxygen containing compounds, often including water combustion reactions are exothermic

What is an acid base reaction

Are reactions that form water upon mixing of an acid and a base

If you could see atoms and molecules what would you look for as conclusive evidence of a chemical reactions

Atoms combining with other atoms to form compounds and original molecules decomposing

Evidence that a chemical reaction has occurred

Color change, formation of a solid or gas, heat absorption or emission, and light emission

What are the main evidences of chemical reaction

Color change, the formation of a solid, the formation of a gas, the emission of light, and the emission or absorption of heat

What is a combustion reaction

Combustion reactions create CO2 and H2O and always react with an oxygen. They are a type of redox equation

Describe the differences between a molecular equation and a complete ionic equation

Complete ionic equation shows how they are actually present in the solution, where as an molecular equation shows the complete neutral formulas for every compound in the reaction

Solubility rules

Compounds containing Li+, Na+, K+, NH4+, NO3-, C2H3O2- Are mostly soluble with no exceptions Cl-, Br-, I-, are mostly soluble except when any these ions pair with Ag+, Hg2 2+, or Pb2+, the compound is insoluble. SO4 2-, is soluble except when paired with Sr 2+, Ba2+, Pb2+, or Ca2+, the compound is insoluble. OH-, S2-, are mostly insoluble except when either of these ions pairs with Li+, Na+, K+, or NH4+, than the compound is soluble. CO3 2-, PO4 3-, are mostly insoluble except when either of these ions pairs with Li+, Na+, K+, or NH4+, the compound is soluble

A compound is insoluble if it

Doesn't dissolve in the liquid

Net ionic equation

Equations which only show the species that actually participate in the reaction

G

Gas

Acid base reactions (also called neutralization reactions)

Generally form water and an ionic compound called salt that usually remains dissolved in the solution

A compound is Soluble in a particular liquid

If it dissolves in that liquid

Spectator ions

In a complete ionic equation, some of the ions in the solution appear unchanged on both sides of the equation. They don't participate in the reaction

How do ionic compounds dissolve in water

Ionic compounds when dissolved in water usually dissociate into their component ions

What is a redox equation

Is a reaction involving the transfer of electrons

What is a chemical reaction?

Is the change of one or more substances into different substances

Fundamental definition of oxidation

Is the loss of electrons, and a fundamental definition of reduction is the gain of elections

L

Liquid

Oxidation and reduction must

Occur together

Displacement reactions

One element displaces another in a compound

Key to predicting precipitate reactions

Only insoluble compounds form precipitates. Two solutions containing soluble compound precipitates

Oxidation reduction reactions

Or redox equations are reactions involving the transfer of electrons Many redox reactions involve the reaction of a substance with oxygen. However redox equations need not involve oxygen.

The substances on the right side are called the

Products

Gas evolution reactions

Reactions that evolve a gas. Like precipitate reactions, these reactions occur when the cation Of one reactant combines with the anion of another

Precipitation reactions

Reactions that form a solid or precipitate upon mixing two aqueous solutions they are the most common reactions in chemistry

Acid base reactions

Reactions that form water upon mixing of an acid and a base

Gas evolution reactions

Reactions that occur in liquids and form gas

Complete ionic equation

Shows the reactants and products as they are actually present in the solution

Synthesis or combination reactions

Simpler substances combine to form more complex substances

S

Solid

Strong electrolytes

Substances that completely dissociate into ions in solution

What is a strong electrolyte solution

Substances that completely dissociate into ions in solution are called electrolytes

Many chemical reactions can be classified into the following 4 categories:

Synthesis or combination reactions, decomposition reactions, displacement reactions, double displacement reactions

Aqueous solution

The most common reactions, they are a homogeneous mixture of a substance with water.

Will the precipitate in a precipitate reaction always be a compound that is soluble or insoluble?

The precipitate will always be insoluble, it is the solid that forms upon mixing two aqueous solutions

The substances on the left side of the equation are

The reactants

Strong electrolyte solution

The resultant solutions

Precipitation reaction

They form solid substances in water

Decomposition reactions (extra)

They require energy in the form of heat, electrical current, or light to make them happen. This is because compounds are normally stable and energy is required to decompose them.

Double displacement reactions

Two elements or groups of elements in two different compounds exchange places to form two new compounds

How do Polyatomic ions within ionic compounds dissolve water

When ionic compounds containing Polyatomic ions dissolve in water, the Polyatomic ions usually dissolve as intact units