A 5.000-g soil sample was analyzed for potassium content by extracting the potassium using 10.00 mL aqueous ammonium acetate solution. Following the extraction, the soil was filtered and rinsed. The filtrate with rinsings was diluted to exactly 50.00 mL. Then, 1.00 mL of this solution was diluted to 25.00 mL, and this dilution was tested with an instrument. The concentration in this 25.00 mL was found to be3.18 ppm. What is the concentration of the potassium in the soil in ppm

A 5.000-g soil sample was analyzed for potassium content by extracting the potassium using 10.00 mL aqueous ammonium acetate solution. Following the extraction, the soil was filtered and rinsed. The filtrate with rinsings was diluted to exactly 50.00 mL. Then, 1.00 mL of this solution was diluted to 25.00 mL, and this dilution was tested with an instrument. The concentration in this 25.00 mL was found to be3.18 ppm. What is the concentration of the potassium in the soil in ppm

Fundamentals Of Analytical Chemistry

9th Edition

ISBN:9781285640686

Author:Skoog

Publisher:Skoog

Chapter8: Sampling, Standardization, And Calibration

Section: Chapter Questions

Problem 8.1QAP

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0.56 g 1,4‐dimethoxybenzene, 0.9 mL 2‐chloro‐2‐methylpropane, 5 mL nitrobenzene and 0.52 g graphite were combined, and the mixture was refluxed for 1.5 hours. It was then cooled to room temperature and filtered. The filtered graphite was washed with 15 mL hexane. The filtrate was distilled under vacuum to remove any remaining 1,4‐dimethoxybenzene, 2‐chloro‐2‐ methylpropane and nitrobenzene (6.3 g), yielding 0.44 g 1,4‐di‐tert‐butyl‐2,5‐dimethoxybenzene (43.4% yield). What is the Atom economy, E factor, and effective mass yield?
You obtain an Unknown Sample from the Stockroom. You begin testing the solution through the steps outlined in the flowchart of the experiment’s PDF file. You first add HCl and centrifuge your mixture. You observe the formation of a white precipitate in the bottom of the test tube. After pouring off the supernatant liquid, you add hot water to the white precipitate. Upon addition of the hot water, you have some white precipitate still at the bottom of the test tube, and the supernatant liquid is poured off. To this liquid, potassium chromate (K2CrO4) is added. Upon this addition of potassium chromate, you observe no formation of precipitate. Which of the following is a valid conclusion to draw at this point? (Choose one.) Select one: 1. Hg22+ is definitely present. 2. Pb2+ is NOT present. 3. Ag+ is definitely present. 4. Pb2+ is definitely present.
A student weighed approximately 1.5 g of an unknown solid acid and carefully placed the sample in a clean, but not necessarily dry, 250.0 mL volumetric flask. The student added deionized water to the flask, swirled the solution until the solid acid dissolved, then added sufficient deionized water to fill the flask to the fill line. A volumetric pipet was used to transfer 25.00 mL of the resulting solution to an Erlenmeyer flask, and 2 – 3 drops of phenolphthalein were added.The student filled the sodium hydroxide buret and titrated the acid solution with standardized 0.1000 M NaOH to the first permanent faint pink color, then repeated the titration a second time.Your instructor will provide the mass of unknown solid acid, as well as the initial and final buret readings for the two titrations. From this data and the information above, you will be able to calculate the molar mass of the unknown acid.The unknown solid acid is diprotic; that is, there are two moles of ionizable H+ ions per…
A student weighed approximately 1.5 g of an unknown solid acid and carefully placed the sample in a clean, but not necessarily dry, 250.0 mL volumetric flask. The student added deionized water to the flask, swirled the solution until the solid acid dissolved, then added sufficient deionized water to fill the flask to the fill line. A volumetric pipet was used to transfer 25.00 mL of the resulting solution to an Erlenmeyer flask, and 2 – 3 drops of phenolphthalein were added.The student filled the sodium hydroxide buret and titrated the acid solution with standardized 0.1000 M NaOH to the first permanent faint pink color, then repeated the titration a second time.Your instructor will provide the mass of unknown solid acid, as well as the initial and final buret readings for the two titrations. From this data and the information above, you will be able to calculate the molar mass of the unknown acid.The unknown solid acid is diprotic; that is, there are two moles of ionizable H+ ions per…
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Following the monograph procedure, a 724-mg of aspirin (MW-180 g/mol) dissolved in 18.5 ml of cold neutralized alcohol. This solution was then initially titrated with 0.101 N sodium hydroxide solution, then later neutralized with 0.104 N sulfuric acid. What is the percentage purity of sample?
You obtain an Unknown Sample from the Stockroom. You begin testing the solution through the steps outlined in the flowchart of the experiment’s PDF file. You first add HCl and centrifuge your mixture. You observe the formation of a white precipitate in the bottom of the test tube. After pouring off the supernatant liquid, you add hot water to the white precipitate. Addition of the hot water dissolves some of the precipitate, but some white precipitate still remains on the bottom of the test tube. You pour off the supernatant liquid, and add ammonia (NH3) to the remaining precipitate. You now observe the formation of a gray-black precipitate. Which of the following is a valid conclusion to draw at this point? Select one: Hg22+ is definitely present. Pb2+ is definitely present. Ag+ could be present, or Hg22+ could be present, or BOTH could be present. Ag+ is definitely present
You obtain an Unknown Sample from the Stockroom. You begin testing the solution through the steps outlined in the flowchart of the experiment’s PDF file. You first add HCl and centrifuge your mixture. You observe the formation of a white precipitate in the bottom of the test tube. After pouring off the supernatant liquid, you add hot water to the white precipitate. Addition of the hot water dissolves some of the precipitate, but some white precipitate still remains on the bottom of the test tube. Which of the following is a valid conclusion to draw at this point? Pb2+ is definitely present. Hg22+ is definitely present. Ag+ could be present, or Hg22+ could be present, or BOTH could be present. Ag+ is definitely present