Author: Anonymous

Using the table below, answer the following questions about the peptide composed of  the amino acids: Arg-Glu-Ala-Asp.   Use the letters above each structure to answer the following questions: What Amino Acid structure above is the amino acid Arg ? [drop1] What Amino Acid structure above is the amino acid Glu? [drop2] What Amino Acid structure above is the amino acid Ala? [drop3] What Amino Acid structure above is the amino acid Asp? [drop4] Using the pKa values provided, what would be the charge on the peptide at a pH of 6? [drop6] Using the pKa values provided, what is the PI of this peptide? [drop7]

Heat, changes in pH, and changes in salt concentration can cause a protein to denature. Explain how these 3 factors would cause denaturation. Be SPECIFIC in the effects each would cause and on what structures.

Many anabolic reactions require the input of large amounts of energy tosynthesize large molecules. Explain how a cell provides that energy at body temperatures. 

Buffer systems usually consist of a weak acid and a weak base, and together they help to keep the pH of thecell, blood, tissue fluid, etc., within a critical range. The carbonic acid – bicarbonate ion buffer system helpsto regulate blood pH. The following chemical equation describes the chemical reactions of this buffer system.  H2CO3 HCO3- + H+ Examine the chemical equation and explain how this system works to regulate any increases or decreases inpH that may take place.

Titanium has a body-centered cubic unit cell. The density of titanium is 4.50 g/cm³. Calculate the atomic radius of titanium in angstroms. (1 Å = 10⁻¹⁰ m;  a=4r√3)

   Above is the phase diagram for Benzene along with its structure and some of its thermodynamic data. Using the information provided, answer the following questions about Benzene: What is the most dense phase at 5.5 oC: solid, liquid, or gas?           [phase1] Does the melting point increase or decrease as pressure is applied? [phase2] What is the normal boiling point of benzene?       [phase3] At what temperature would pure benzene boil in Denver, where atmospheric pressure is around 0.82 atm?  [phase4]     

For each of the substances below, match it to the type of colloid it represents:

The boiling point of pure ethanol is 78.4 °C. A solution is made using 100.0 g of ethanol (the solvent) (MM = 46.07 g/mol) and 12.1 g of methanol (MM = 32.04 g/mol). What is the boiling point of this solution? (Kb of ethanol is 1.22 °C/m)

A 10.00% by mass aqueous solution of Hydrogen Bromide has a density of 1.046 g/mL. What is the molality of the solution?

Define the following terms and give 1 example molecule for each: Strong Electrolyte, Weak Electrolyte and Non-Electrolyte