Acid-Base Titrations (Applications) Flashcards
These Standard acids are commonly standardized using Na2CO3
strong acids
Titration of a standard acid with sodium
carbonate yields two endpoints at about _________ and __________.
pH 8.3, pH 3.8
The ______________ is always used for standardization because the change in pH is greater. Sharper
second end point
more obvious color change
sharper endpoints
_________________ (more obvious color change) are achieved by boiling the solution briefly to eliminate the the reaction product, carbonic acid, and carbon dioxide.
Sharper endpoints
For ________________, NaOH is standardized against potassium acid phthalate, KHC8H4O4 commonly abbreviated as KHP. Sodium hydroxide is usually prepared by dissolving the solid NaOH with carbon
standard bases
absorption of carbon dioxide by a base solution introduces a systematic error called ________________ and decreases the sharpness of endpoints during titration.
carbonate error
Calculations involved in __________________ are straight-forward like any strong acid-strong base calculations.
standardization
introduced by Johan Kjeldahl
Kjeldahl Method
It is the most widely used analytical method for determining nitrogen content.
Kjeldahl method
Example substances that contain nitrogen include:
- amino acids
- proteins
- synthetic drugs
- fertilizers
- explosives
- soils
- potable water supplies
- dyes
These are performed on a variety of substances such as meat, feed, grain, wastewater, soil, and many other samples.
Kheldahl nitrogen determinations
The _____________ is determined by a neutralization titration.
ammonia
The ___________________ is distilled, and collected in an acidic solution.
liberated ammonia
Solutions containing a mixture of sodium carbonate, sodium hydrogen carbonate, and sodium hydroxide, either alone or as various mixtures, are usually analyzed through______________________.
acid-base titrations.
The Kjeldahl method consists of three steps, which must be carefully carried out in sequence:
- Digestion
- Neutralization and Distillation
- Titration
alkaline-range indicator
phenolphthalein
acid-range indicator
bromocresol green
Two titrations with a _________________ are utilized to analyze the composition of a carbonate mixture.
strong acid
Two titrations with a strong acid are utilized to analyze the composition of a ___________________.
carbonate mixture
example of substances that contain nitrogen
amino acids
proteins
soils
explosives
dyes
Kjeldahl nitrogen determinations
are performed on a variety of substances such as meat, feed, grain, wastewater, soil, and many other samples.
are ions that do not participate in the reaction and do not affect the equilibrium of the system.
spectator ions
is the summarized reaction including ions that participated in the reaction (the spectator ions were omitted).
net ionic equation
The equilibrium constant for a system involving a slightly soluble salt and its corresponding ions in a saturated solution is the
solubility product constant
is expressed as the concentration of the “dissolved solid” in a saturated solution This may be solved by using the Ksp of the salt
molar solubility or the solubility of a salt