Lab 5 REPORT FORM_F22_V2

Do not give handwriting solution.

given the following results " create a “standard curve” (a graph) that shows the concentration on the x-axis and the absorbance on the y-axis" and "a solution of copper(II) sulphate with an unknown concentration was found to have an absorbance of 0.09. Use your standard curve to determine its concentration" ample Number Concentration of Copper(II) Sulphate (mM) Measured Absorbance 1 0   0 2 50   0.12 3 100 0.24   4 150   0.35 5 200   0.47 Unknown   40 0.09

PLEASE Answer within 20-30 minutes. Thank you!

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

1. A company illegally dumped their wastewater on a river bank. You are part of an environmental NGO that are tasked to determine what kind toxins that may have contaminated the waters. What kind of analysis would you do? a. Characterization analysis b. Qualitative analysis c. Fundamental analysis d. Quantitative analysis 2. Four groups weighed ten rock samples each, and tested the possibility of outliers using Q-test. At 95.0% confidence (a = 0.05), which of the following is considered to be an outlier?  a. 0.024 b. 0.413 c. 0.453 d. 0.674 3. An unknown solution containing oxalic acid, which is a diprotic acid, is titrated against sodium hydroxide. How many mole/s of titrant is needed to react with one mole of analyte?  a. ½ b. ¼ c. 2 d. 4

Construct a calibration curve based on the following data: Concentration Fe 0.100 0.500 2.00 4.00 7.00 (ppm) Absorbance 0.0122 0.0608 0.2322 0.455 0.5858 Use LINEST to find the slope and intercept and their uncertainties. Enter your answer as a number with no units to three significant figures. 0.085 0.037 b m 0.100 0.500 Sm Sb r2 0.958 0.037 Sy

Beaker Volume of KSCN No solution 1 0.50 mL 9.50 mL Part I: Data for Calibration Graph Accurate Concentration of potassium thiocyanate, KSCN stock solution: 0.001 M 0.2 M Fe(NO3)3- Iron(III)nitrate solution: 0.5M Volume of HNO3 solution 0.2 M Volume of 0.2 M Fe(NO3)3 solution 10.00 mL Absorbance 0.037 2 1.00 mL 9.00 mL 10.00 mL 3 2.00 mL 8.00 mL 10.00 mL 4 3.00 mL 7.00 mL 10.00 mL 0.122 0.313 0.547 5 4.00 mL 6.00 mL 10.00 mL 6 5.00 mL 5.00 mL 10.00 mL 0.791 0.868

Using the data below, please create a calibration graph and determine the concentration of the unknown sample. Standard #1 Standard #2 Standard #3 Unknown sample Concentration 1.5 x 10 M 2.0 x 103 M 2.5 x 10 M ? Absorbance 0.61 0.80 0.98 0.72 a) 1.6 x 10 M b) 1.8 x 10° M c) 2.1 x 103M d) 2.2 x 10 M

For the data below, if a diluted (DF=100) water sample has an absorbance of 0.057, calculate the number of Cu atoms in a 100 mL sample. Answer using 3 significant figures. For Scientific Notation use this pattern example 6.02x10^23 Cu mg/L Absorbance 0 0.002 2 0.045 4 0.093 6 0.133 8 0.177 0.197 10

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

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The first photo is the data, second photo is the question! thank you!

Graph data with Concentration on the x-axis and Absorbance on the y-axis. Find the line of best fit for your data points. Record the respective formula in y=mx+b.

A water sample was analyzed for iron content using the iron-phenanthroline method. Using the set of data from Question 15 (as presented below), Reagent Blank Absorbance Absorbance (au) Reagent Blank Absorbance 0.003 Concentration of Stock Solution: 10 ppm Volume of Stock Solution (mL) Total Volume of Standard Solution (mL) 0.50 10.00 1.00 10.00 2.00 10.00 3.00 10.00 4.00 10.00 5.00 10.00 Volume of Trial Unknown Solution (mL) 1 5.00 2 5.00 3 5.00 find the true concentration of Fe2+ of the original sample. A) 5.12 ppm B) 2.56 ppm 2.52 ppm D) 5.05 ppm Concentration of Standard Solution (ppm) Total Volume of Unknown Solution (mL) 10.00 10.00 10.00 Absorbance (au) 0.012 0.132 0.267 0.349 0.428 0.560 Absorbance (au) 0.289 0.296 0.281

PART ONE: Preparation of FECNS* Solution Prepare the two solutions in table 1 by accurately measuring the required volumes of distilled water and CNS into two labeled test tubes. The absorbance of the solutions must be measured soon after adding the Fe" solution from a buret. TABLE 1 Fe 5 ml 5S mL Solution Distilled Water CNS 2 mL Total Volume 3 ml 2 ml 10 ml 3 mL 10 ml In this part of the experiment you are to explore what the above quote means. As a PRELIMINARY Exercise, formulate a hypothesis as to what would happen under each of the following circumstances: 1. 1ml of 0.0020 M CNS' solution is added to the unused portion of solution 1 in the test tube 2. One drop of 0.20 M CNS solution is added to the unused portion of solution 2 in the test tube.

Table 1. pH of water samples Sample No. Water Samples pH 1 Tap water from household 6.59 2 Water from creek 7.35 3 Water from river 7.35 4 Unknown sample 7.00 Table 2. Absorbance of Samples Table 3. Calibration Curve Data* Sample No. Absorbance Absorbance 3- Concentration of PO4 Ions, ppm (1 pt each) 1 1.33 1.0 0.050 2 3.26 2.0 0.093 0.89 3.0 0.137 4 0.099 4.0 0.185 5.0 0.230 *Provided by the instructor II. Graph Determination of Phosphate Concentration 3- 1. Using Excel, plot the concentration of PO4* (x-axis) vs. absorbance (refer to Table 3) The olot must show the equation of the best-fit (or trend) line of the graph. Attach the graph below

Consider the following data set: Sample 1 2 3 4 5 Diluted Unknown (25% dilution) Diluted Unknown (50% dilution) Undiluted Unknown Absorbance at 470 nm 0.032 0.058 0.090 0.114 0.140 0.072 0.138 0.210 Concentration 1.00 x 10-³ M 2.00 x 10-³ M 3.00 x 10-³ M 4.00 x 10-³ M 5.00 x 10-³ M 1. Using MS Excel, plot a calibration curve for samples 1 to 5 (Attach a printed copy of the graph). Determine the molar absorptivity. 2. Calculate the concentration of the diluted and undiluted unknown using the linear regression equation produced from #1. 3. Back-calculate the concentration of the undiluted unknown using the calculated concentration of the 25% and 50% diluted unknown from #2. 4. Explain any significant difference that you see between the concentration of the undiluted unknown that is back-calculated from the absorbance of the 25% and 50% diluted unknown, and the concentration that is directly calculated from the absorbance of the undiluted unknown. 77

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.

How can I solve this question? I need full detail and accurate answer.

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).

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

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

Methods of Analysis Test #1: Polarity, or Effect of a charged rod on a stream of liquid: This test was used to determine the relative polarity of the unknown liquid. The liquid was allowed to run out of a buret and a charged rod was brought up next to the stream. The observations were reported as to whether or not the stream of liquid responded to the charged rod and to what degree. Try this at home with water and a plastic spoon. Rub the plastic spoon against a sweater and move it close to a small stream of water running out of your faucet! Test #2: Volatility, or Rate of Evaporation: A thermometer probe was wrapped with a strip of filter paper. This assembly was soaked in one of the liquids for one minute. The probe was removed, and the temperature change was monitored as the liquid evaporated. The results are given in Graph 1 below. (See Graph)   Graph 1: The curves generated of the change in temperature over time for the substances acetone, hydrogen monoxide, ethylene glycol,…

Please help me graph this on a graph like this .

10 Use contrastive analysis to think about how the following conversion might be done. Then write the steps required for the following conversion to take place -Br

AP Questions // Questions 10 - 11) A student creates four solutions with varying concentration of FeSCN2 and gathers the following data at 298 K using a spectrophotometer calibrated to 460 nm: [FESCN] Absorbance 1.1 x 10-4 M 0.076 1.6 x 10-4 M 0.112 2.2 x 10-4 M 0.167 2.5 x 10-4 M 0.199 On the axis below, create a Beer's Law calibration plot for [FESCN2*]. Draw a best-fit line through your data points.

mix 500 ml of 0.1 M HCl solution with 300 ml of 2 M Ba (OH) 2 solution a) indicate the environment of the solution after mixing b) What color will the detectors, phenophthalein and litmus get?

+3 +2 Na MgO Li +1 Ca N -1 SF Al Br -2 H -3 Reset Help

4. You prepare several dilutions of an unknown compound. You measure the absorbance of each solution at 340 nm using a 1 cm cuvette (your results are listed in the table below). What is the extinction coefficient (in (M•cm)') of the compound? (Hint: assume that each of the individual values contains some degree of experimental error.) Concentration(uM) Absorbance at 340 nm 10.0 0.011 20.0 0.023 40.0 0.066 80.0 0.119 160.0 0.189

Given this data, if a CV solution has an absorbance of 1.125, what is [CV]? [CV] / M              A  1.0 × 10–6 M      0.250 3.0 × 10–6 M      0.750     Question 12 options:   4.5 × 10–6 M   5.0 × 10–6 M   5.5 × 10–6 M

= O ORGANIC FUNCTIONAL GROUPS Naming and drawing unsubstituted amides Draw the skeletal ("line") structure of N,N-dimethylethanamide. Click and drag to start drawing a structure. C™ X с S E 1/5 Kir

2 What methods are used to sep X G In Part Il of experiment 5, a 1:1: X + u/ultra/courses/_393452_1/cl/outline * Question Completion Status: QUESTION 3 After you complete the second step, you will be left with a clear colorless liquid. What should be done to the liquid to finish the separation? O Heat the mixture to evaporate the liquid O Add a base to neutralize the solution. O Nothing - you are done since you have a pure, clear, colorless substance O Add the residue back to the solution and dry. QUESTION 4 In Part II of experiment 5, a 1:1:1 mixture of sand, salt, and salicylic acid must be separated. Order the following steps necessary to separate this mixture into three pure, dry solids. Filter the liquid leaving a filtrate with just salt dissolved and a residue of sand. v Add hot water to the residue obtained in two steps prior to this one. Filter the liquid leaving a filtrate with just salicylic acid dissolved and a residue of salt and sand. v Heat the filtrate obtained in two…

■ True or False: in a TOF analyzer, a fragment of low mass reaches the detector first ▪ In GCMS when we know what analytes we are measuring we use not know what analytes are in the sample we use than scan. ▪ A) Scan; SIM ■ B)SIM; scan • C) SIM; SIM mode. When we do mode. SIM allows greater sensitivity