Problem Set

Satisfactory Essays
GENERAL BIOCHEMISTRY
Problem Set No. 1
Answered by: Andrea Rose A. Fajardo of BSFT 2-1N

1. Calculate the pH of a dilute solution that contains a molar ratio of potassium acetate to acetic acid (pKa=4.76) of: a. 2:1 pH = 4.76 + log[2]/[1] = 4.76 + 0.3010 = 5.06 b. 1:4 pH = 4.76 + log[1]/[4] = 4.76 + (-0.6021) = 4.16 c. 6:5 pH = 4.76 + log[6]/[5] = 4.76 + 0.0792 = 4.81 d. 2:3 pH = 4.76 + log[2]/[3] = 4.76 + (-0.1761) = 4.58 e. 9:1 pH = 4.76 + log[9]/[1] = 4.76 + 0.9542 = 5.71 2. A buffer contains 0.01mol of lactic acid (pKa=3.86) and 0.05mol of sodium lactate per liter. a. What is the resulting pH of the buffer? pH = 3.86 + log[0.05]/[0.01] = 3.86 + 0.6990 = 4.56 b. Calculate the change in pH when 5mL of 0.5M HCl is added to 1L of buffer. 5mL of 0.5 mol/L 5mL * 1L/1000mL = 0.005L 0.005L * 0.5 mol/L = 0.0025mol NaC3H5O3 = 0.05mol - 0.0025mol = 0.0475 C3H5O3 = 0.01mol - 0.0025mol =0.0075 pH = 3.86 + log[0.0475]/[0.0075] = 3.86 + 0.8016 = 4.66 • 4.55-4.66 = 0.11 is the change in pH c. What pH change would you expect if you added the same quantity of HCl to 1L of pure water? [H+] = (0.0025mol)(1L) = 0.0025M pH = -log 0.0025 = 2.60 3. The structure of the amino acid of isoleucine is given at the right. a. How many chiral centers does it have? 2 b. How many optic isomers? 4 c. Draw the perspective formulas for all the optical isomers of isoleucine.

[pic]

4. A peptide has the sequence: Glu-His-Trp-Ser-Leu-Arg-Pro-Gly a. What is the charge of the molecules at pH 4 and 11? (Use pKa values of those in the ppt)
|pH

You May Also Find These Documents Helpful

  • Satisfactory Essays

    Problem Set

    • 438 Words
    • 2 Pages

    Math – 213 Problem Set Solve each of the following problems. 1. A coin is tossed four times. What is the probability that at least 2 heads will occur? 2. A pair of dice is rolled. What is the probability that the sum is equal to the following? a. 5 b. 10 c. at most 9 d. at least 8 3. A chip is drawn at random from a jar containing 8 red, 2 blue, 3 green, 4 yellow, and 3 white chips. Determine the probability that it is: a. Red b. Yellow or red c. Not orange 4. In a graduating class of 300 students…

    • 438 Words
    • 2 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Problem Set

    • 676 Words
    • 3 Pages

    Me1 Problem Set #2 The US College Enrollment and the “Third Law of Demand” A theorem proposed by Professors Alchian and Allen in their text, University Economics (1964) has had several rebirths of interest in the literature. The so-called “third law of demand,” or “relative price theorem,” holds that a fixed cost added to a good of varying quality causes the consumer to prefer the category considered of higher quality to the lower. Recently a number of studies, keeping this theorem in mind have…

    • 676 Words
    • 3 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Problem Set

    • 1188 Words
    • 5 Pages

    Energy 1. A man climbs on to a wall that is 5 m high and gains 2200 J of potential energy. What is the mass of the man? Given: Formula: h = 5 m m = PE/gh PE = 2200 J Solution: m = 2200 J / (9.8 m/s2 x 5 m) m = 49 kg 2. Calculate the kinetic energy of a 500 kg car travelling at 50 m/s. Given: Formula: m = 500 kg KE = mv2/2 v = 50 m/s Solution: KE = 500 kg x (50 m/s)2 / 2 KE = 625 000 J Power 3. Riley climbs a flight of stairs in 3 minutes. If he…

    • 1188 Words
    • 5 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Problem set

    • 1065 Words
    • 5 Pages

    1. EP Enterprises has the following income statement. How much net operating profit after taxes (NOPAT) does the firm have? Sales $1,800.00 Costs 1,400.00 Depreciation 250.00 EBIT $ 150.00 Interest expense 70.00 EBT $ 80.00 Taxes (40%) 32.00 Net income $ 48.00 a. $81.23 b. $85.50 c. $90.00 EBIT $150.00…

    • 1065 Words
    • 5 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Problem set

    • 390 Words
    • 2 Pages

    ECE 302 Problem Set 9 Fall 2013 The following problems have been selected from the course text. 4.78 In a large collection of wires, the length of a wire is X, an exponential random variable with mean 5π cm. Each wire is cut to make rings of diameter 1 cm. Find the probability mass function for the number of complete rings produced by each length of wire. 4.85 The exam grades in a certain class have a Gaussian pdf with mean m and standard deviation σ. Find the constants a and b so that…

    • 390 Words
    • 2 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Problem Set

    • 464 Words
    • 2 Pages

    BE 13.8 Vertical analysis (common-size) percentages for Vallejo Company’s sales, cost of goods sold, and expenses are listed below: VERTICAL ANALYSIS 2012 2011 2010 Sales 100.0% 100.0% 100.0% Cost of goods sold 60.5 62.9 64.8 Expenses 26.0 26.6 27.5 Net Income 13.5 10.5 7.7 Did Vallejo’s net income as a percent of sales increase, decrease, or remain unchanged over the 3 year period. Provide numerical support for your answer. Sales – Cost of Goods Sold – Expenses = Net Income 100 – 64.8…

    • 464 Words
    • 2 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Practise Problem Set

    • 509 Words
    • 3 Pages

    ECSE 443- introduction to Numerical Methods in EE Practice Problem Set – Chapter 4 (Note: This problem set is for extra practice. It is not for credit, and not to be handed in) Question 1: Suppose that in a study, several measurements were made to determine a particular quantity for different values of . The collected data are summarized in the following table: 1.0000 5.8823 1.5000 2.0000 2.5000 3.0000 3.5000 4.0000 4.5000 5.0000 5.5000 6.0000 8.8823 17.8821 11.8822 14.8826 26.8825 24.8822…

    • 509 Words
    • 3 Pages
    Satisfactory Essays
  • Satisfactory Essays

    Problem set 5

    • 900 Words
    • 15 Pages

    ECONOMETRICS: PS5 PROBLEM SET 5: ESTIMATION PROBLEMS 1 We have the following variables: Y: Food expenditure in USA. X: Family income. P: Price index. Two different regressions are estimated with the following estimation results (standard errors are in brackets): Coefficient for Regression X Y/P Y / X; P 0.112 (0.003) Coefficient for P 2.462 (0.407) -0.739 (0.114) Determination coefficient 0.614 0.978 Assuming that the true equation for Y includes both X and…

    • 900 Words
    • 15 Pages
    Satisfactory Essays
  • Good Essays

    Problem Set 2

    • 922 Words
    • 4 Pages

    Problem Set 2 Name: __________________________________________ Problem Set 2 is to be completed by 11:59 p.m. (ET) on Monday of Module/Week 4. 1. The following table presents data for wages in the market for internet security professionals. (HINT: in the labor market the roles are reversed. Those who want to hire labor are the demanders. The workers enter the work force providing labor to the market place so they are the suppliers.) Wage Quantity Demanded Quantity Supplied $50,000…

    • 922 Words
    • 4 Pages
    Good Essays
  • Satisfactory Essays

    Problem Set 3

    • 294 Words
    • 2 Pages

    PROBLEM SET 3 Name: ________________________________________ Problem Set 3 is to be completed by 11:59 p.m. (ET) on Monday of Module/Week 6. 1. Data for the market for graham crackers is shown below. Calculate the elasticity of demand between the following prices. Price of crackers Quantity Demanded (per month) $3 80 $2.5 120 $2 160 $1.5 200 $1 240 $1.00 - $1.50: ___________________________________ $1.50 - $2.00: ___________________________________ $2.00 - $2.50: ___________________________________…

    • 294 Words
    • 2 Pages
    Satisfactory Essays