Ch. 18 Solubility, Titrations! Flashcards
What are buffers? What is the composition and purpose of buffers?
Solutions that resist a change in pH by neutralizing added acid or base. They are typically 2 components; 1 to react w/ added base, 1 to react w/ added acid
What is the Common ion effect?
When a solution contains a common conj. ion of the acid or base.
If HC2H3O2 sol’n contained C2H3O2-, pH would change significantly less.
What is an Acid-base titration?
a basic OR acidic sol’n of unknown concentration reacts w/ the titrant(acidic or basic sol’n of KNOWN concentration).
What is the equivalence point of a titration?
The point when # of mol of base is stoichiometrically equal to # of mol of acid.
What are the 3 types of titrations? (Week 7, Pg.1!!!)
- Strong acid titrated w/ Strong base: pH=7 at equiv.!
- Weak acid tit. w/ a Strong base: pH>7, basic!
- Weak base titrated w/ Strong acid: pH<7, acidic. curve is the same, but reverse of the 2nd!
What does it mean for a compound to be soluble/insouble?
If a compound dissolves in Water, it is soluble.
How do common ions in a sol’n effect solubility?
The solubility of ionic compound is lower in a sol’n containing a common ion, than it is in pure H2O.
How does pH effect solubility?
The higher the pH in Insoluble Hydroxides, the less soluble(and vice versa)
The higher the pH in Salts of Weak Acids, the more soluble these salts are.
What is a precipitate? When do precipitates occur?
A precipitate is a solid formed in a sol’n. Precipitation occurs when a sol’n is OVER saturated (Q>Ksp).
What is the difference between the reaction quotient(Q) and Solubility Product Constant(Ksp)
The Q and Ksp are measured similarly(Ex; [A+][X-]) however, Ksp is at equilibrium, while Q is not!
How is Qualitative Analysis used with solubility?
using solubility rules to determine the presence of certain ions.
What is a complex ion? how can the formation of these be calculated?
Complex ions contain a central metal ion bound to 1 or more ligands. These can be found using the formation constant!
