Chemistry

3. Consider the reaction between 25.00 mL of 0.120 M CH3COOH with 15.00 mL of 0.120 M NaOH. a. How many mmol of CH3COOH are dissolved in 25.00 mL of 0.120 M CH3COOH?

3. Consider the reaction between 25.00 mL of 0.120 M CH3COOH with 15.00 mL of 0.120 M NaOH.a. How many mmol of CH3COOH are dissolved in 25.00 mL of 0.120 M CH3COOH? b. How many mmol of NaOH are dissolved in 15.00 mL of 0.120 M NaOH? c. The limiting reactant is _________________ while the …

3. Consider the reaction between 25.00 mL of 0.120 M CH3COOH with 15.00 mL of 0.120 M NaOH. a. How many mmol of CH3COOH are dissolved in 25.00 mL of 0.120 M CH3COOH? Read More »

Derive a titration curve for 50.00 mL of 0.0100 M Sr2+ with 0.0200 M EDTA in a solution buffered to pH 11.0. Calculate pSr values after the addition of 0.00, 10.00, 24.00, 24.90, 25.00, 25.10, 26.00, and 30.00 mL of titrant.

EXPERT ANSWER Initial [Sr2+] = 0.0100 M Initial volume of Sr2+ solution = 50.00 mL Initial milimoles of Sr2+ = 50 * 0.010 = 0.5 mmoles At pH = 11, 4 of EDTA = 0.85 KSrY = 4.3×108 Conditional constant, K’SrY =  4 * KSrY = 0.85 * 4.3×108 = 3.655×108 When 0.0 mL EDTA is added – [Sr2+] = 0.010 M …

Derive a titration curve for 50.00 mL of 0.0100 M Sr2+ with 0.0200 M EDTA in a solution buffered to pH 11.0. Calculate pSr values after the addition of 0.00, 10.00, 24.00, 24.90, 25.00, 25.10, 26.00, and 30.00 mL of titrant. Read More »

Which analyte will have a greater change of pAg at equivalence point region? I- (iodide) or IO3-(iodate)?

EXPERT ANSWER Answer: This is the Iodometric involes indirect titration of iodine liberated by reaction with an analyte,whereas iodometry involes direct titration using iodine as titrant. Redxc titration using sodium thiosulphate as a reducing agent is known as iodometric titration since it is used sphecifically titrate iodine.In this titratio starch is used as indicator since …

Which analyte will have a greater change of pAg at equivalence point region? I- (iodide) or IO3-(iodate)? Read More »

1. Data A. Effect of substrate Concentration Color Code tt A (2 vol catechol:4 vol water) tt B (4 vol catechol:2 vol water) tt C (6 vol catechol) ++ B. Effect of Enzyme Concentration Color Code tt A (5 drops enzyme extract) tt B (10 drops enzymes extract) ++ tt C (15 drops enzyme extract) +++ Construct a plot in Excel showing enzyme activity (y-axis) versus amount of enzyme extract (x-axis). For enzyme activity use the following conversion of color code to numerical value: + = 1; += 2; and +++ = 3. Note: Place all graphs of this experiment in one file and upload it. C. Temperature and Enzyme Action Color Code tt A (0°C) ++ tt B (37°c) +++ tt C 170°C) Construct a plot in Excel showing enzyme activity (y-axis) versus temperature (x-axis). For enzyme activity use the following conversion of color code to numerical value: += 1; ++ = 2; and +++ = 3. D. Effect of pH on Enzyme Activity Color Code tt A (HCI, PH= 1) tt B (lactic acid, pH = 5) tt C (distilled water, pH = 7) +++ ft DNA củ, PH = 9] ++ Construct a plot in Excel application showing enzyme activity (y-axis) versus pH (x-axis). For enzyme activity use the following conversion of color code to numerical value: += 1; ++ = 2; and +++ = 3. II. Questions 1. Based on the graph constructed in Part A, give a statement relating enzyme activity to substrate concentration. 2. Explain why at 70C enzyme activity decreased. 3. On what type of solution – acidic, basic, or neutral – will polyphenoloxidase work best. Explain your answer.

EXPERT ANSWER ANSWERS) 1.the more concentrated the substrate is within a solution, the more frequently substrate molecules will randomly collide with the enzyme in the proper orientation for the active site to bind to the substrate, and thus the more often substrate will be converted into product..So in general the rate of an enzyme-catalyzed reaction …

1. Data A. Effect of substrate Concentration Color Code tt A (2 vol catechol:4 vol water) tt B (4 vol catechol:2 vol water) tt C (6 vol catechol) ++ B. Effect of Enzyme Concentration Color Code tt A (5 drops enzyme extract) tt B (10 drops enzymes extract) ++ tt C (15 drops enzyme extract) +++ Construct a plot in Excel showing enzyme activity (y-axis) versus amount of enzyme extract (x-axis). For enzyme activity use the following conversion of color code to numerical value: + = 1; += 2; and +++ = 3. Note: Place all graphs of this experiment in one file and upload it. C. Temperature and Enzyme Action Color Code tt A (0°C) ++ tt B (37°c) +++ tt C 170°C) Construct a plot in Excel showing enzyme activity (y-axis) versus temperature (x-axis). For enzyme activity use the following conversion of color code to numerical value: += 1; ++ = 2; and +++ = 3. D. Effect of pH on Enzyme Activity Color Code tt A (HCI, PH= 1) tt B (lactic acid, pH = 5) tt C (distilled water, pH = 7) +++ ft DNA củ, PH = 9] ++ Construct a plot in Excel application showing enzyme activity (y-axis) versus pH (x-axis). For enzyme activity use the following conversion of color code to numerical value: += 1; ++ = 2; and +++ = 3. II. Questions 1. Based on the graph constructed in Part A, give a statement relating enzyme activity to substrate concentration. 2. Explain why at 70C enzyme activity decreased. 3. On what type of solution – acidic, basic, or neutral – will polyphenoloxidase work best. Explain your answer. Read More »

D. Substrate Specificity of Polyphenoloxidase Enzyme Activity (Color Intensity) +++ enzyme extract + catechol (tt A) + enzyme extract + phenol (tt B) enzyme extract + hydroquinone (tt C) ++ SF 幻四口回& e$ 七 Arrange the three test tubes according to decreasing order of color intensity. Test Tube A > Test Tube C > Test Tube B

EXPERT ANSWER The addition of catechol, i.e. 1,2-dihydroxybenzene, to test tube A increases the color intensity because of the fact that the two fluorophores (two hydroxy groups, adjacent to each other) present in the catechol increase Enzyme Activity rapidly. The addition of hydroquinone, i.e. 1,4-dihydroxybenzene, to test tube C increases the color intensity because of …

D. Substrate Specificity of Polyphenoloxidase Enzyme Activity (Color Intensity) +++ enzyme extract + catechol (tt A) + enzyme extract + phenol (tt B) enzyme extract + hydroquinone (tt C) ++ SF 幻四口回& e$ 七 Arrange the three test tubes according to decreasing order of color intensity. Test Tube A > Test Tube C > Test Tube B Read More »