C483 Exam 1 Questions and Correct
Answers/ Latest Update / Already
Graded
Solubility
Ans: depends on dielectric constant and polarity
like dissolves like
Residue
Ans: Monomers in a polymer
Free Energy
Ans: Energy Available to do work in a system or reaction
Enthalpy
Ans: total heat or energy of a system
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entropy
Ans: A measure of disorder or randomness.
intramolecular forces
Ans: Forces within molecules
H-Bonds
Dipole-Dipole
LDF
van der Waals
Hydrophobic Effect
Ans: Exclusion of nonpolar substances from an aqueous solution
Non-polar molecules do not interact wiht H2O
Amphipathic compounds
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Ans: Compounds with both hydrophobic and hydrophilic portions (ex.
phospholipids in cell membranes)
Auto-Ionizations
Ans: H2O "self-ionizes" in solution and "proton jumping" occurs where water
molecules can create a network in solution so that the "acid" is spread out
across the solution and all the water molecules are moving and
transferring protons around to create hydronium
pH
Ans: Concentration of hydrogen ions in a solution (-log [H+])
pKa
Ans: -log (concentration of products/ concentration of reactants)
pH of strong acid solutions
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Ans: strong acids completely dissociate in solution
amount and strength of acid affects pH change
little strong acid in
solution can sometimes change pH more than more weak acid in solution
Weak Acids
Ans: do not completely dissociate in solution
lower Ka and higher pKa
Henderson-Hasselbalch
Ans: pH = pKa + log[A-][HA]
A- = proton acceptor
HA = proton donor