Pre-lab 5 - Beer's law(2)

A. Copper sulfate pentahydrate is often used to teach students about Beer’s Law by making a standard curve (linear regression). The bright blue color of the solution has a peak absorbance in the red range of the electromagnetic spectrum. The absorbance value is proportional to concentration. How many grams of CuSO4 5H2O to make up 250 mL of a 0.2 M stock of this solution? B. Using M1V1 = M2V2 how many mL would a student need to measure out in graduated cylinder to make up a 50 mL (V2) solution of 0.1M, 0.05 M, 0.025M 0.0125M solutions for a standard curve at the peak wavelenth for this compound? I need help with part B of this question.

A. Copper sulfate pentahydrate is often used to teach students about Beer’s Law by making a standard curve (linear regression). The bright blue color of the solution has a peak absorbance in the red range of the electromagnetic spectrum. The absorbance value is proportional to concentration. How many grams of CuSO4 5H2O to make up 250 mL of a 0.2 M stock of this solution? B. Using M1V1 = M2V2 how many mL would a student need to measure out in graduated cylinder to make up a 50 mL (V2) solution of 0.1M, 0.05 M, 0.025M 0.0125M solutions for a standard curve at the peak wavelenth for this compound?

If a solution has an absorbance of 2 you can be certain that  the solution is highly diluted and needs to be concentrated  all the statements are correct  this is a reliable absorbance and downstream analysis can be done  the solution is highly concentrated and needs dilution

When using a spectrophotometer to measure concentration of a solution, which of the following absorbance readings would indicate the highest concentration? 1. 0.56 2. 0.32 3. 1.34 4. 1.28

23. How do you set up and solve absorbance problems like this?

If A=absorbance, B=molar absorptivity, C=length of light path, D=concentration, and you plot a graph of absorbance (y-axis) vs concentration (x-axis), what does the slope of the Beer's Law (A=BCD) curve signify? Choose one:  a. absorbance b. molar absorptivity c. length of light path d. concentration

A series of six solutions was prepared at the given concentrations. Sample AB C D E F Concentration (mM) 50 100 | 150 | 200 300 400 The absorbance of each solution was then measured using a colorimeter. Sample A B C D E F Absorbance 0.25 0.50 0.75 1.00 1.50 2.00 What is the concentration of the solution with an absorbance of 1.50? C = mM

please can you please im begging can you please create graphs with Excel (or a similar program). Plot absorbance (v-axis) vs. A (×- axis) for the absorbance curve determined in part 2. Connect the points with a smooth curve. Plot absorbance (y-axis) vs. concentration (x-axis) for the Beer's Law data from part 3. Draw a best-fit line or use a program such as Excel and do a least-squares fit to determine the best-fit line through the points. please answer super super fast please please need it now its urgent just creat the graphs

Given the following standard curve of Absorbance vs Concentration (mM), what in the concentration of Aspirin if the absorbance is 0.822?

Using the following data, if an unknown solution of Orange Dye X had a measured absorbance of 0.345, what is the concentration Orange Dye X in the solution?  Concentration (mM)  Absorbance 0.005 0.143 0.010 0.285 0.015 0.428 0.020 0.570

em1.png chem3.png Part 3: Q9 Average absorbance Flask 8 Flask 9 Flask 10 Flask 11 Part 3: Q9 Flask 8 Flask 9 Flask 10 Flask 11 Part 3: Q10 Flask 8 Flask 9 Flask 10 Flask 11 Q Part 3 0.146 [Fe] -0.002mol/L 0.166 volume 5.00mL 0.215 0.294 [FESCN mol/L) ✪ 4.59* 10 5.18*10* 6.64 x 10 9.08*10* [Fe(mol/L) 5.00 x 10 5.00*10* Y=3362x -0.0083 R¹ 0.9993 5.00 x 10 5.00*10* (Amounts of flask 8 (9 - 11's values are in the spreadsheet) 1:1 Ratio so, Molarity of Fe(NO3))3 = 0.2M Volume of Fe(NO3))3 = 5.00mL 71% Moles of Fe³= Molarity x volume(L) Moles of Fe = 0.2M × 0.005L = 1× 10-³mole 68% [SCN ](mol/ 4 x 10-4 5 x 10-4 7*10* 1*10* الخا chem2.png Concentration of Fe³ 9, X = mole of Fe³1x10³ mole Volume 0.0054 Ⓒ 8, Average absorbance for solution 8 (same for 9 - 11) Average absorbance for flask 8 = sum of all absorbances / number of readings (0.145 +0.147 +0.148) 3 Using equation of calibration curve's line(slope) of best fit, the average absorbances of the unknown concentrations to determine…

A sample in a 1cm cuvette gives an absorbance reading of 0.6. If the absorptivity for this sample is 15000 L/mol*cm, what is the molar concentration of the sample?

please please answer super fast i need it before 9:30pm please answer all

1. Given the following values, use the absorbance formula to find the     hemoglobin concentration of the unknown.   As =0.600 Au =0.300 Cs =20g/dl   2. Convert 12.8 g Hb into percent Hb   3. Compute the grams Hb of 88% Hb.

Table II Cuvette # Concentration Absorbance 0.50 M 1 1.049 2 0.40 M 0.926 3 0.20 M 0.740 0.298 4 0.10 M 5 0.05 M 0.202 Unknown # 9 0.427 Unknown # 10 7 0.646 Blank (DI water) 0 1. If Beer's Law is valid, the value of "E" should be constant. Use A = E*C*L or E= A/(E*L) and the data from Table II to calculate values of E for the five solutions below The value of L is normally 1 cm so E = A/C in this experiment. Table III Solution # Calculated Values of E 1 2 3 4 5

25. How would you set up and solve concentration problems like this which involve absorbance?

How would I do 2? the concentration iron is 1.85mg/vitamin tablet, and the absorbance at 508nm is 0.37

A direct ELISA experiment was done to determine the amount of protein present in a sample. A standard curve was prepared by plotting log Absorbance versus log concentration of protein in (ng/mL). The equation of the line is Y= 0.895 X -1.25. If an unknown protein shows an absorbance of 1.23. Calculate the concentration of this protein in the sample in (ng/mL).

in the images attach can you please calculate the Concentration of Allura Red M and can you also please please Create graphs with Excel (or a similar program). Plot absorbance (v-axis) vs. A (×- axis) for the absorbance curve determined in part 2. Connect the points with a smooth curve. Plot absorbance (y-axis) vs. concentration (x-axis) for the Beer's Law data from part 3. Draw a best-fit line or use a program such as Excel and do a least-squares fit to determine the best-fit line through the points. lastly can you please show a sample the concentration of the solutions made by dilution. Also use the slope of the best-fit line from your absorbance vs. concentration plot to calculate the concentration of Allura Red in each unknown. Also please dont forget to do the results box in the image attach please please answer super super fast i really need it its very urgent and important please answer everything i need it before the end of today before 11:59pm I would really appreciate it if…

Absorbance 1.40 Beer's Law Plot 1.20 1.00 0.80 0.60 0.40 0.20 0.00 0 10 20 30 40 50 Concentration (M x 105) D The slope for the line is 80.23. Use the Beer's Law plot provided to determine the concentration for a solution with absorbance = 0.5786. M

em1.png Part 3: Q9 Average absorbance Flask 8 Flask 9 Flask 10 1:1 Ratio so, Flask 11 Part 3: Q Flask 8 Flask 9 Flask 10 Flask 11 Part 3: Q10 Flask 8 Flask 9 Flask 10 Flask 11 Part 3 0.146 0.166 [Fe] -0.002mol/L 0.215 0.294 [FESCN³mol/L) 4.59% 10 5.18*10* 6.64*10* 9.08*10* [FXmol/L) 5.00 *10* 5.00*10* Y=3362x-0.0083 R² = 0.9993 5.00*10* 5.00*10* (Amounts of flask 8 (9 - 11's values are in the spreadsheet) 71% volume 5.00mL Molarity of Fe(NO3))3 = 0.2M Volume of Fe(NO3))3 = 5.00mL Moles of Fe³= Molarity x volume(L) Moles of Fe¹ = 0.2M X 0.005L = 1x10-³mole x [SCN][mol/ 4x10 5×10-4 7x10 1×10 1 Concentration of Fe³ = mole of Fe³ Volume mole of Fe³1x10³ mole G.O05L 8, Average absorbance for solution 8 (same for 9 - 11) Average absorbance for flask 8 = sum of all absorbances / number of readings (0.145 +0.147 +0.148) 3 Using equation of calibration curve's line(slope) of best fit, the average absorbances of the unknown concentrations to determine [FeSCN-Jat equilibrium in solution 8:…

Chemistry

What solution concentration gives an absorbance of 1.00?   Question 8 options:   6.46 × 10–4 M   6.83 × 10–4 M   6.91 × 10–4 M

How do I find Concentration? flask Calculate solution Concentration (M) Volume stock of 0.40 M CuSO4 (ml) Volume of flask (ml) Absorbance at 635 nm(a.u.) 1   2.0 10 .185 2   4.0 10 .362 3   6.0 10 .510 4   8.0 10 .674 5   10.0 10 .843

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