Chapter 8 Chemistry
A chemical equation represents, with symbols and formulas, the identities and relative molecular or molar amounts of the reactants and products in a chemical reaction.
Is the process by which one or more substances are changed into one or more different substances.
In any chemical reaction, the orginal substances are known as the reactants.
The reuslting substances from a chemical reaction are called the products.
Signs of a Reaction
Evolution of energy as heat and light.
Production of a gas.
Formation of a precipitate.
A change in color.
A solid that is produced as a result of a chemical reaction in a solution and that seperates from the solution is known as a precipitate.
Proper Chemical Equation
A properly written chemical equation can summarize any chemical change.
The equation must represent known facts and contain correct formulas for the reactants and products.
The law of conservation of mass must be satisfied.
Placing a coefficient in front of a formul a specifies the relative number of moles of the substance.
Is a small whole number that appears in fron tof a formula in a chemical equation.
An equation in which the reactants and products in a chemical equation are represented by words. A word equation has
Represents the reactants and products of a chemical reaction by their symbols or formulas.
Is a chemical reaction in which the products re-form the orginal reactnats.
Chemical Equations are balanced by .. .
The adding of coefficents.
Significance of a Chemical Equation
Chemical equations are very usedul in doing
Chemical Equations Don't
An equation gives no indication of whether a reaction will actually occur. They also give no indication of the speed of which a reaction will occur.
aka Composition Reaction happens when two or more substances combine to form a new compound.
Represented by the equation A + X ---> AX
A single compound undergoes a reaction that produces two or more simpler substances.
Represented by the formula AX ---> A + X
Decomposition takes place when . . .
Most decomposition reactions take place only when energy in the form ofd electricity or heat is added.
The decomposition of a substance by an electric current is called electrolysis.
aka Replacement Reaction, happens when one element replaces a similar element in a compound.
A+ BX ---> AX + B
Y + BX ---> BY + X (Halogens)
The ions of two compounds exchange places in an aqueous solution to form two new compounds.
AX + BY ---> AY + BX
In a combustion reaction, a substance combines with oxygen, releasing energy in the form of heat and light.
Hydrocarbon/Alcohol + Oxygen ----. Carbon Dioxde & Water
Is a list of elements organized according to the ease with which the elements undergo certain chemical reactions. Activity series are also useful in predicting whether a chemical reaction will occur.
Activity Series . . .
Chemist determine activity series through experiments.
Chapter 8 Chemistry
Gen Chem Chapter 8