Ch 4. Reactions in an Aqueous Solution Flashcards
Solution
a homogenous mixture of two or more substances
Solvent
the substance present in the greatest quantity in a solution
Solutes
the other substance in a solution that are not the solvent
Electrolyte
a substance whose aqueous solutions contain ions
nonelectrolytes
a substance that does not form ions in a solution
Solvation
helps stabalize the ions in a solution and prevents cations and anions from recombining.
Dissociation
when an ionic substance dissolves in H2O, the solvent pulls the individual ions from the crystal and solvates them
Are most molecular compounds nonelectrolytes?
True
What molecular compounds are electrolytes
Acids
Strong Electrolytes
are solutes that exist in a solution completly or nearly completly as ions
Weak Electrolytes
solutes that exist in solutions mostly in the form of neutral molecules with only small fractions in the form of ions
Chemical Equilibrium
a state in which the relative numbers of each type of ion or molecule in the reaction are constant overtime.
Precipitation Reactions
reactions that result in the formation of an insoluble product
Precipitate
an insoluble solid formed by a reaction in a solution
Soluble Ionic Compounds
NO3- CH3COO- Cl- Br- I- SO4-
Exceptions to NO3- solubility
None
Exceptions to CH3COO-
None
Exceptions to Cl- Solubility
Pb 2+, Hg 2+, Ag +
Exceptions to Br- solubility
Pb 2+, Hg 2+, Ag +
Exceptions to I- solubiltiy
Pb 2+, Hg 2+, Ag +
Exceptions to SO4- solubiltiy
Sr 2+, Ba 2+, Hg 2+, Pb 2+
Insoluble compounds
S 2-
CO3 2-
PO4 2-
OH -
Exception to insoubility of S 2-
NH4 +, alkali Metals, Ca 2+, Sr 2+, Ba 2+
Exceptions to insolubility of CO3 2-
NH4 +, Alkali Metals
Exceptions to insolubility of PO4 2-
NH4 +, Alkali Metals,
Exceptions to insolubility of OH-
NH4 +, Alkali Metals, Ca 2+, Sr 2+, Ba 2+
Metathesis Reaction
AX + BY —> AY + BX
Molecular Equations
Shows the chemical formulas without indicating ionic characters
Complete Ionic Equations
A chemical equation in which dissolved strong electrolytes are written as seperate ions
Spectator Ions
ions that appear in identical form on both sides of a complete ionic equation and play no role in the reaction
Net ionic equation
includes only the ions and molecules directly involved in the reaction
Strong Acids
HCl HBr HI HClO3 HClO4 HNO3 H2SO4
Strong Bases
LiOH NaOH KOH RbOH CsOH Ca(OH)2 Sr(OH)2 Ba(OH)2
Acids
substances that ionize in aqueous solutions to form H+
-proton donors
Monoprotic acids
yield 1 H+
diprotic acids
yield 2 H+
Bases
substances that accept H+ ions and produce OH- ions in water
- a proton exceptor
- they do not have to contain OH-
Strong Electolytes are
Ionic
strong acids and bases
Weak Electrolytes are
Weak acids and Bases
Nonelectolytes
All molecular compounds that are not acids or bases
Neutrilization reaction
when a soultion of an acid and base are mixed
salt
any ionic compound whose cation comes from a base and whose anion comes from a acid
Oxidation-reduction reaction/ redox reaction
reactions in which electrons are transferred from one reactant to another
Oxidation
Loss of electrons by a substance
Reduction
the gain of electrons by a substance
oxidation numbers/states
a positive or negative whole number assigned to an element in a molecule or ion on the basis of a set of formula rules
Displacement reactions
the ion in the solution is displaced/replaced through oxidation of an element
Activity Series
a list of metals arranged in order of decreasing ease of oxidation
-any metal on the list can be oxidized by the ions of elements below it
Active metals
react most readily to form compounds
-alkali metals and alkaline earth metals
Noble metals
are very stable and form less readily
-near the bottom of the table
Concentration
designates the amount of solute dissolved in a given quantity of solvent or quantity of solution
Molarity (M)
expresses the concentration of a solution as the number of moles in a liter of solution
- a conversion factor between volume of a solution and moles of solute
Molarity Formula
M= Moles of solute/Volume of solution in Liters
Dilution
adding water to concentrated solutions
-moles of solute before dilution = moles solute after dilution
Dilution Formula
M1 x V1 = M2 x V2
Titration
involves combining a solution where the solute concentration is not known with a reagent solution of known concentration called a standard solution
Equivalence Point
the point at which stoichiometrically equivalent quantities are brought together