Exp 6

1. On the molecular level, what does it mean for a solid sample to be pure? 2. The computed percent recovery was more than 100%. What does this signify, and what should be done about it?

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

Based on this. What was the percentage error in the percentage of water in the sample, compared to pure MgSO4•7H2O?

1a. Throughout the experiment, what are some possible sources of error that could have led to someone recovering a significantly smaller amount of table salt (NaCI) than was originally present in the sample mixture. 16. What are some possible sources of error that could have led to someone to appear to have recovered a significantly larger amount of sand (SiO2) than was originally present in the sample mixture.

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

What type of chemical analysis would you use for the following?  1. 500 milligrams of ascorbic acid in vit. C 2. determination of sodium, glucose, alkaline phosphate, and others in a blood analysis 3. four percent calcium and two percent iron is found in an analysis of pineapple juice   [Spectroscopy, gravimetric analysis, volumetric analysis, electroanalytical methods, OR chromatography]

Please don't provide handwritten solution ....

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

5. Why is decantation rather than filtration the preferred method of separating the salt from the mixture? 12:03 AM

19.

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?

1. a. Calculate the mass of BaSO4 required to make 50.00 mL of a 0.1500 M solution. b. Calculate the absolute uncertainty in the molar mass of BaSO4. c. Calculate the absolute uncertainty in the concentration, assuming that the balance is calibrated and precise to ±0.1 mg and that the volumetric flask is calibrated and precise to 0.05 mL.

sity o... Fingsbo... ckboard... EARED4 Method? 7... 9 2 W 6 9 QUESTION 5 One mole of copper(II) sulfate, CuSO4, contains 2.41 x 1023 2.41 x 1024 6.02 x 1023 1.51 x 1023 4 Click Save and Submit to save and submit. Click Save All Answers to save all answers. 3 16 MAF 1 23 H R T moles of O. tv Y 8 Save All Answers 8 0.22 S

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

only need help with "e" 1. Use the following data table and steps a-d below to calculate the concentration of the zinc carbonate. The mass of the filter paper alone (no ZnCO3) was 1.3457 g. The Zn(NO3)2 solution (10.00 mL) was mixed with 15.00 mL of the 1.00 M Na2CO3. a. Calculate the mass of zinc carbonate formed. 0.8939 b. How many moles of zinc carbonate formed? 0.00715 c. Calculate the moles of zinc in the zinc nitrate solution used. 0.00175 d. Calculate the concentration of the zinc in the zinc nitrate solution. 0.715 M e. Confirm whether sodium carbonate was in excess. Using the concentration of the sodium carbonate solution used, determine how many moles were used and confirm it was the excess reagent

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

An 8 mL volumetric pipet is used to collect a sample from a 0.2015 M solution of NaOH. a. Estimate the uncertainties in volume and concentration. b. Calculate the moles of NaOH in the sample. c. Use error propagation to find the uncertainty in moles of NaOH.

You were tasked to separate the components of a mixture containing silica, sodium chloride and charcoal. TNāCI dissolves in water while silica and charcoal are not water-soluble. Only charcoal dissolves in carbon disulfide. a. Write a short experimental procedure to carry out the separation of the mixture. b. Given the following data, determine the percentage of charcoal, sodium chloride and silica. Mass (g) Mass of beaker 100.000 Mass of beaker + mixture 110.000 mass of evaporating dish 62.000 mass of evaporating dish + solid after evaporation of water 65.000 Mass of beaker + charcoal + silica after evaporation of excess water 117.000 mass of beaker + silica after decanting dissolved charcoal and drying 113.545

Give me answer of d and e

I need help with this and use the model (Not honor class) (Not grading)

Subject: chemistry

Supply the missing information in the table. (Given in Blue). Answers in scientific notation should be in this sample format >>> 1.0 x 10-14

Calculate the pH of the following solutions prepared by: Part A Dissolving 4.7 g of lithium hydroxide in water to give 290 mL of solution. Express your answer to two decimal places. pH- Submit Part B Request Answer Dissolving 0.91 g of hydrogen chloride in water to give 0.35 mL of solution. Express your answer to two decimal places. pH = Submit Bequest Answer