Exam 1 Vocab Flashcards
What is a buffer?
A buffer is a solution that resists change in pH, consisting of a weak acid and it’s conjugate base, or a weak base and it’s conjugate acid.
What is the common ion effect?
The common ion effect is a phenomenon that is responsible for the reduction of solubility of an electrolyte in a solution when one of the ions present in that electrolyte is already in the solution.
What is the Henderson-Hasselbach equation?
And equation used to determine the pH and concentrations of an acid and base in a buffer solution. pH = pKa + log ([A-]/[HA]) where A- is the molar concentration of the base and HA is the molar concentration on the acid.
What is a titrant?
A titrant is a solution of know composition and concentration that is added to a solution of unknown concentration in order to determine the concentration of the second solution.
What is a 100% neutralization reaction?
A reaction between an acid and a base in which they are both completely “used up” to form water.
What is the equivalence point?
The equivalence point is the point in a titration where the added titrant and the original solution are both stoichiometrically equal (the same number of moles of each are present)
What is an end point?
The end point is the point at which the titration is complete (having reached a certain pH), as determined by an indicator added to the solution at the beginning of the titration.
What is an indicator?
An indicator is a substance added to a titration to signal (by means of color change) when a titration is complete (having reached a certain pH). Different indicators change color at different pH numbers.
What is phenolphthalein?
Phenolphthalein is a chemical that is colorless in acidic solutions and pink in basic solutions. It is used as an indicator in titrations. It’s chemical formula is C20H14O4
What is a solution?
A solution is a mixture of chemicals where the dissolved chemical (the solute) is evenly distributed in the dissolving chemical (the solvent)
What are saturated, unsaturated and super saturated solutions?
Saturated: a solution containing the maximum possible amount of solute
Unsaturated: a solution in which more solute could be dissolved
Supersaturated: a solution in which more than the maximum possible amount of solute is dissolved. Usually heated above room temperature.
What are Ksp and Qsp?
Ksp: the solubility product constant. It is the equilibrium constant for a solid dissolving in an aqueous solution.
Qsp: the ion product quotient. It is the measure of concentration of a solution when the solution is not at equilibrium.
QspKsp, then solution is super saturated
What is solubility?
Solubility is the ability of a given substance (the solute) to dissolve in to another given substance (the solvent)
What is selective precipitation?
It is a method by which ions can be removed from a solution. An specific anion or cation is added to a solution, which reacts with only one of the other ions at a certain concentration to form a precipitate, which can then be removed from the solution.
What is a complex ion?
A complex ion is a charged molecule with a metal ion bonded to one or more molecules or ions.
