A 0.01kg plant extract in 2dm' of water was shaken with 0.1dm' ether. Upon checking, 1.7x10 kg of plant extract passes into ether. Determine the plant extract left unextracted if the aqueous solution was shaken with 0.1dm' ether the second time. There are no changes on the molecular state of the plant extract.

A 0.01kg plant extract in 2dm' of water was shaken with 0.1dm' ether. Upon checking, 1.7x10 kg of plant extract passes into ether. Determine the plant extract left unextracted if the aqueous solution was shaken with 0.1dm' ether the second time. There are no changes on the molecular state of the plant extract.

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter33: Automated Methods Of Analysis

Section: Chapter Questions

Problem 33.8QAP

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Oral rehydration salts are stated to contain the following components: Sodium Chloride 3.5g Potassium Chloride 1.5g Sodium Citrate 2.9g Anhydrous Glucose 20.0g 8.342 g of oral rehydration salts are dissolved in 500 ml of water. 5 ml of the solution is diluted to 100 ml and then 5 ml is taken from the diluted sample and is diluted to 100 ml. The sodium content of the sample is then determined by flame photometry. The sodium salts used to prepare the mixture were: Trisodium citrate hydrate (C6H5Na3O7, 2H2O) MW 294.1 and sodium chloride (NaCl) NW 58.5. Atomic weight of Na = 23. The content of Na in the diluted sample was determined to be 0.3210 mg/100 ml. Determine the % of stated content of Na in the sample. The stated should be 104.5, how??
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