Exp 6

Gravimetric analysis is a quantitative method that involves measurement of volume of a solution of known concentration which is used to determine the concentration of the analyte.  True  False   A good example of complete analysis is the determination of %C, %H and %O in an unknown organic sample.  True  False

please highlight the correct answer

1. Explain both precision and accuracy as they pertain to chemical measurements.  2. Why would you use the method of standard addition to calibrate a measurement instead of a calibration curve?

What are replicates in Analytical Chemistry? O The component of a sample that repeats over different assays. Similar assays done to different samples A sample that contains exactly the same amount of analytes than the original sample similar samples that are analyzed at the same time and in the same way

alculate the approximate volume of the vinegar sample needed for the analyses (Part A.1). Brand of vinegar or unknown no. Colauita tof White Wine Trial 1 1122809 Trial 2 Trial 1 Trial 2 e Guia 112.280g (12.822g 112.796 115 565 lis.9 1. Mass of flask (g) l15.603 2. Mass of flask + vinegar (g) 2.496 3.323 2,743 2,749 3. Mass of vinegar (g) B. Analysis of Vinegar Sample 2mL 7.5 23mL 32.コ 1. Buret reading of NaOH, initial (mL) 5.25mL 13ML amL 2. Buret reading of NaOH, final (mL) 33,3 31.2 1. Volume of NaOH used (mL) 2! mL a7.45 me 20.3 32.2 o i135 • 004 1 Molar concentration of NaOH (mol/L) Oi135 • 00 3 1003 , 063 5. Moles of NaOH added (mol) 6. Moles of CH,COOH in vinegar (mol) 7. Mass of CH,COOH in vinegar (g) 8. Percent by mass of CH,COOH in vinegar (%) 9. Average percent by mass of CH,COOH in vinegar (%) Calculations for Trial 1 of the first vinegar sample on next page. Experiment 10 137

8 - 14 please

What are advantages and limitations of different types of modelling? (modelling with experiments, computer simulations, modelling kits and quantitative modelling)

7. You have a 100 µM stock solution of dNTPs in the freezer and are setting up a PCR reaction in which you need to have a final concentration of 20 µM dNTPs. In a reaction volume of 25 μl, how much of your stock dNTPs do you add to each PCR reaction?

Sucrose solution for experiment 1: (Question a-c)Prepare a solution of sucrose by accurately weighing 9.0 – 9.25 g of sucrose into a 100mLbeaker / conical flask. Record the mass of the sample. Add 25 mL distilled water. Mix until allcrystals dissolve.NaCl solution for experiment 2: (Question d-f)Prepare a solution of NaCl by accurately weighing approximately 1.5 g of NaCl into a 100 mLbeaker / conical flask. Record the mass of the sample. Add 25 mL distilled water. Mix until allcrystals dissolve.MgCl2٠6H2O solution for experiment 2: (Question d-f)Prepare a solution of magnesium chloride by accurately weighing approximately 3.6 g ofMgCl2٠6H20 into a 100 mL beaker / conical flask. Record the mass of the sample. Add 25 mLdistilled water. Mix until all the crystals dissolve

See attached. Solve and explain step by step.

duction to MasteringChemistry - Attempt 1 duction to Vocabulary Questions Reset Help maple 1. Hardwoods reproduce using flowers and have broad leaves; hardwoods include trees such as pine cedar elm and pine mango 2. Conifer leaves are generally thin and needle-like, while seeds are contained in cones. Conifers cedar include pine and elm elm 3. Deciduous trees lose their leaves seasonally and include trees such as mango and maple 4. Evergreens are plants that maintain their leaves in all seasons and include trees such as elm pine and cedar Submit Previous Answers Request Answer Introduction to Ma. fa トト」 トI fo fo ins prt sc 8% 8 9 10

The following volumes of 0.000300 M SCN are diluted to 15.00 mL. Determine the concentration of SCN in each sample after dilution. These values will be used during the experiment. To enter exponential values, use the format 1.0e-5. Sample 0.000300 M SCN (mL) [SCN'] (M) 1 1.50 3.50 7.00 4 10.00 3.

3. While determining the volume during this experiment (Part II), if the total volume of the flask were incorrectly reported as 125 mL, how would this error affect the calculated molar mass of the unknown volatile liquid? Explain. MacBook Air 80 DII F3 F4 F5 F6 F7 F8 F9 F10 & * 4 5 6 7 8 R Y * 00

Complete the table by entering the molarity of B2- for each standard solution. Show an illustrative calculation for tube ‘A’. Use the dilution formula and express each result to one more digit than allowed by applying the rules of significant figures. Standard Volume of stock B2- solution taken, mL Molarity of dilute B2 Construct a graph of Absorbance vs. molarity of B2- in Excel using the data in the preceding table. Make certain to title the graph and include axes labels with proper units. Absorbance is dimensionless (has no unit). Add a linear trendline to the graph but do not set the y-intercept to zero Solid M2B is added to 25 mL of water, the resulting mixture is continually stirred for 1 hour. At this point, it is assumed that equilibrium (eqn 3) has been established. The mixture is transferred to a test tube, and the test tube is centrifuged to assure that any residual solid M2B is fully settled out. A portion of the supernatant in the test tube is carefully…

Most analytical machines used in science can either measure absorbance of light, like the spectrophotometers used BioZ 151 and 152 labs, or can measure change in electrical conductance. In order to convert things like absorbance values into concentration data, a linear regression is used. In order to determine nitrite concentration in water samples, nitrite is reacted with several chemicals to produce a purple color. The absorbance of the solution is measured from known amounts of nitrite to produce a standard curve to analyze samples. Use the data in the provided table, or from the linked spreadsheet to make a graph and perform a linear regression using treadline. mg/L NO3 Absorbance 0 0.1 0.3 0.5 0.7 o 0.183 0.542 0.914 1.298) 1.61) In order for this to work, samples must be diluted prior measurement so that the concentration falls within the range of the standard curve. If a sample underwent a 30 dilution, and produce an absorbance value of 0.953, what is the resultant concentration…

What volume of 0.220 M NaOH, in milliliters, contains 45.0 g of NaOH? Volume mL %3D

Please help with the % Error relative to label.

pour it 2. Still sleepy from a late night studying, you take the milk out of the refrigerator and pour it on your lemon juice to milk to make paneer (fresh cheese). As a group, craft a chemical explanation for the fact of coagulated milk onto your cereal. The last time you saw milk coagulate like that was when you added breakfast cereal. Unfortunately, by the time you notice the funny smell you have already poured clumps lemon juice to milk to make paneer (fresh cheese). As a group, craft a chemical explanation foea added that spoiled milk coagulates.

IA 8A Periodic Table of the Elements H Не 2A 3A 4A SA 6A 7A 1.008 4.003 3 5 6 8 9 10 Li Be F Ne 2 6.941 9.012 10.81 12.01 14.01 16.00 19.00 20.18 12 13 14 15 16 17 18 Na Mg Al Si Cl Ar 3B 4B 5B 6B 7B 8B IB 2B 22.99 24.31 26.98 28.09 30.97 32.07 35.45 39.95 19 20 21 22 23 24 25 26 27 Čo 28 29 30 31 32 33 34 35 36 K Са Sc Ti Cr Mn Fe Ni Cu Žn Ga Ge As Se Br Kr 39.10 40.08 44.96 47.87 50.94 52.00 54.94 55.85 58.93 58.69 63.55 65.41 69.72 72.64 74.92 78.96 79.90 83.80 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 Rb Sr Zr Nb Mo Tc Ru Rh Pd Ag | Cd 54 Xe In Sn Sb Te (98) 112.4 127.6 85.47 87.62 88.91 91.22 92.91 95.94 74 W 101.1 102.9 1064 107.9 114.8 1187 121.8 126.9 131.3 55 56 57 72 73 75 76 77 78 79 80 81 82 83 84 85 86 Cs Ва La Hf Ta Re Os Ir Pt Au Hg Pb Ро At Rn 132.9 137.3 1389 178.5 180.9 183.8 186.2 190.2 192.2 195.1 197.0 200.6 2044 207.2 209.0 (209) (210) (222) 87 88 89 104 105 106 107 108 109 110 II 112 113 114 115 116 117 118 Fr Ra |Ac Rf Db Sg Bh Hs Mt Ds Rg Cn Nh F1 Mc…