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| 7255619639 | State the unusual properties of water and explain why these properties are observed (include the shape of the water molecule and ability to form hydrogen bonds) | High melting + boiling point (b/c 4 H bonds between other water molecules -lots of energy to break H bonds) high heat of vaporization (same) Shape of water comes from two H atoms sharing electrons with one O atom (BENT). There is two bonds with H atoms and 2 with nonbonding orbitals making it nearly tetrahedron. This makes it polar creating attraction to bond to other water molecules. Hydrogen bonds occur because O is partially - while H's are partially +. This in turn causes the -O to hydrogen bond with the partial H+ from another water molecule, vice versa. This is an example of ELECTROSTATIC attraction | 0 | |
| 7255619640 | define Amphipathic | compounds with regions that are polar and nonpolar | 1 | |
| 7255620845 | define bond dissociation energy | energy required to break a bond, for H-bonds (23 kJ/mol) | 2 | |
| 7255620846 | define clathrates | crystalline compounds of nonpolar solutes and water. Ordering of water molecules reduces entropy. (causes water to become highly ordered.) | 3 | |
| 7255621914 | define colligative properties | solutes change certain physical properties of a solvent, water: vapor pressure, boiling point, melting point (freezing point), and osmotic pressure. | 4 | |
| 7255621915 | define hydrogen bond | Weak electrostatic attraction between one electronegative atom (N, O, F) and a hydrogen atom covalently linking to a second electronegative atom EX: interaction between the oxygen atom of one water molecule and the adjacent water molecule's hydrogen, due to electrostatic interactions. | 5 | |
| 7255622828 | define hydrophilic | compounds that dissolve easily in water because they are "water-loving" | 6 | |
| 7255622829 | define hydrophobic | compounds that do not dissolve easily in water because they are "water-fearing" | 7 | |
| 7255623650 | define hydrophobic interactions | forces that hold the nonpolar regions of molecules together. Strength is not due to any nonpolar parts, rather from a system of thermodynamic stability by minimizing the number of ordered water molecules required to surround hydrophobic portions of the solute molecules. | 8 | |
| 7255623651 | define hypertonic (solution) | osmolarity is higher than that of the cytosol of a cell, cell shrinks as water moves out. | 9 | |
| 7255623652 | define hypotonic (solution) | osmolarity is lower than that of the cytosol of a cell, cell swells as water moves in. | 10 | |
| 7255624675 | define isotonic (solution) | solution's osmolarity is equal to that of the cell's cytosol | 11 | |
| 7255624676 | define micelles | An aggregate of amphipathic molecules in water, with the nonpolar potions in the interior and the polar potions at the exterior surface, expose to water. | 12 | |
| 7255626583 | define osmolarity | Concentration of solution in terms of solutes per liter of solution. | 13 | |
| 7255626584 | define osmosis | water movement through a semipermeable membrane driven by differences in osmotic pressure, important in life of most cells | 14 | |
| 7255628995 | define van der waals interactions | two dipoles (different molecules) weakly attracted to each other (polarization), bringing two nuclei closer | 15 | |
| 7255631195 | Draw a diagram of the structure of ice and discuss the characteristics of the hydrogen bonding observed in ice and why ice is less dense than liquid water | Figure 2.2 solid water (ice) can form a maximum of four H-bonds, creating regular crystalline lattice which makes the ice less dense than water. (spaced evenly between). Water only has an average of 3.4 H-bonds and is spaced out more. | 16 | |
| 7255632766 | Describe the interactions involved when polar and ionic solutes dissolve in water | Polar molecules dissolve in water because the partial negative part of the polar molecule attracts the partial positive hydrogen atom in water. Thus there is a change from solute-solute H-bond interaction. (polar biomolecules dissolve readily in water because they can replace water-water interactions with more energetically favorable water-solute interactions) Ionic molecules like salts can be hydrated and stabilized by water. For example, NaCl becomes Na+ and Cl- ions which attract water molecules (fig2-6) ion-dipole interaction | 17 | |
| 7255635255 | Compare the types of weak interactions among biomolecules in strength to each other and to covalent bonds | Hydrogen Bonds -between neutral groups and peptide bonds (Carboxyl +amino) Ionic interactions -attraction and repulsion Hydrophobic interactions Van der Waals Interaction All of these interactions have a cumulative effect, thus playing important roles in macromolecular structures. | 18 | |
| 7255636374 | Describe the ionization of water and the extent to which it occurs | Small degree of ionization of water to hydrogen ions (H+) and hydroxide ions (OH-) Water molecules have a tendency to undergo reversible H20 (reversible arrows) (H+) + (OH-) Hydrogen ions are quickly hydrated to Hydronium ions (H30+) | 19 | |
| 7255637671 | Define Kw and know how it is determined; know its value at 25 degrees C | equilibrium constant of water at 25 degrees C The product (55.5M)(Keq) at 25 degrees C = (ion product of water) Kw = [H+][OH-] = (55.5M)(1.8x10^-16M) = 1.0x10^-14M^2 This is the neutral pH where there are exactly equal concentrations of H+ and OH- | 20 | |
| 7255639270 | Calculate pH or pOH at 25 degrees C given the [H+] or [OH-] of a solution | pH = -log[H+] pOH = -log[OH-] pH scale Table 2-6 | 21 | |
| 7255645585 | Calculate pH (or [H+]), pKa (or Ka), or the concentration of a weak acid, given information on two of the three variables | Ka is the ionization constants or acid dissociation constants Ka = [H+][A-] / [HA] = Keq pKa = -log Ka Henderson-Hasselbach Equation: pH = pKa + log (base/acid) | 22 | |
| 7255647772 | Calculate the pH of a buffer or the proportions of conjugate acid and base present in a bugger using the Henderson-Hasselbach equation | Henderson-Hasselbach Equation: pH = pKa + log (base/acid) | 23 | |
| 7255650063 | Discuss how to choose and prepare an effective buffer for a given application | A weak acid and its conjugate base, use the acid that corresponds to the desired equivalence zone from a titration | 24 | |
| 7255650771 | Calculate the change in pH of a buffer when acid or base is added | pg. 66 (2-6) | 25 | |
| 7255654773 | Identify the three reversible equilibria involved in the bicarbonate buffer system in animals with lungs and explain how changes in pH affect these equilibria | H2CO3 = Carbonic Acid (proton donor) HCO3- = Bicarbonate (proton acceptor) C02 (d) = dissolved carbon dioxide LOOK AT "NOTES" |  | 26 |
| 7255656551 | Explain what is meant by acidosis and how untreated diabetes leads to acidosis | Acidosis occurs when the pH of blood is often below the normal value of 7.4 Lack of insulin or the insensitivity to insulin disrupts the uptake of glucose from blood into the tissues and forces the tissues to use stored fatty acid as their primary fuel. This leads to the accumulation of 2 carb acids, beta-hydroxybutyric acid and acetoacetic acid. The dissociation of these acids lead to acidosis. | 27 | |
| 7256815519 | Define condensation reaction | Where elements of water are eliminated after a reaction occurs. (H20 is cleaved from reactants) | 28 | |
| 7256815520 | Define hydrolases | exergonic reaction (release) that uses a catalytic enzyme for hydrolysis | 29 | |
| 7256815907 | Define hydrolysis reaction | Cleavage accompanied by the addition of elements of water. | 30 |
