titration
Experiment 4
SOLUTION STOICHIOMETRY ACID-BASE TITRATIONS
Determination of the Percent Acetic Acid in Vinegar
Objectives: (1) To introduce and use the concept of solution stoichiometry
(2) To specifically use solution stoichiometry to determine the percent of acetic acid in vinegar.
(3) To prepare a standard solution by the method of titration.
Consider the following balanced chemical equations:
(1) HCl + NaOH ------> NaCl + HOH
(2) H2SO4 + 2NaOH --------> Na2SO4 + 2HOH
(3) 2HCl + Ca(OH)2 ---------> CaCl2 + 2HOH
(4) H2SO4 + Ca(OH)2 ---------> CaSO4 + 2HOH
(5) 2H3PO4 + 3Ca(OH)2 ----------> Ca3(PO4)2 + 6H2O
These reactions in water have one feature in common: a hydrogen ion from one compound reacts with a hydroxide ion from the other compound to form water. The compound furnishing the hydrogen ion is called an acid and the one furnishing the hydroxide ion is called a base. The metal ion (the cation) of the base and the anion of the acid combine to form a salt. In this context, salt is essentially synonymous with ionic compound. Reactions such as these are called acid-base reactions.
The concepts of solution reactions and stoichiometry in this experiment are applicable to any chemical reaction taking place in solution, not just the acid base reactions indicated here.
Stoichiometry is the area of chemistry that deals with how much of one compound reacts with another. When compounds are mixed in amounts such that these amounts just exactly react and none of any reactant is in excess (they are all the limiting reagent), this mixture is said to be a stoichiometric mixture or that stoichiometric amounts have been mixed. Observation of the above balanced equations indicates that stoichiometrically reaction occurs so that the total number of hydrogen ions available in the amount of acid reacting is the same as the total number of hydroxide ions
SOLUTION STOICHIOMETRY ACID-BASE TITRATIONS
Determination of the Percent Acetic Acid in Vinegar
Objectives: (1) To introduce and use the concept of solution stoichiometry
(2) To specifically use solution stoichiometry to determine the percent of acetic acid in vinegar.
(3) To prepare a standard solution by the method of titration.
Consider the following balanced chemical equations:
(1) HCl + NaOH ------> NaCl + HOH
(2) H2SO4 + 2NaOH --------> Na2SO4 + 2HOH
(3) 2HCl + Ca(OH)2 ---------> CaCl2 + 2HOH
(4) H2SO4 + Ca(OH)2 ---------> CaSO4 + 2HOH
(5) 2H3PO4 + 3Ca(OH)2 ----------> Ca3(PO4)2 + 6H2O
These reactions in water have one feature in common: a hydrogen ion from one compound reacts with a hydroxide ion from the other compound to form water. The compound furnishing the hydrogen ion is called an acid and the one furnishing the hydroxide ion is called a base. The metal ion (the cation) of the base and the anion of the acid combine to form a salt. In this context, salt is essentially synonymous with ionic compound. Reactions such as these are called acid-base reactions.
The concepts of solution reactions and stoichiometry in this experiment are applicable to any chemical reaction taking place in solution, not just the acid base reactions indicated here.
Stoichiometry is the area of chemistry that deals with how much of one compound reacts with another. When compounds are mixed in amounts such that these amounts just exactly react and none of any reactant is in excess (they are all the limiting reagent), this mixture is said to be a stoichiometric mixture or that stoichiometric amounts have been mixed. Observation of the above balanced equations indicates that stoichiometrically reaction occurs so that the total number of hydrogen ions available in the amount of acid reacting is the same as the total number of hydroxide ions