A company is producing a powder which can be reconstituted as a healthy drink for the elderly. Analysis of the powder for calcium involved using the following procedure. 4 g of powder was reconstituted to 150 ml with water. Thirty ml of 24 % TCA was added to 30 ml of this solution. The mixture was allowed to stand for 15 mins and then filtered. The filtrate was analysed for calcium using atomic absorption spectroscopy. From the standard curve it was found that the reading for the analysed sample was 24mg/litre. Calculate the concentration of calcium in the powder (mg/kg).

A company is producing a powder which can be reconstituted as a healthy drink for the elderly. Analysis of the powder for calcium involved using the following procedure. 4 g of powder was reconstituted to 150 ml with water. Thirty ml of 24 % TCA was added to 30 ml of this solution. The mixture was allowed to stand for 15 mins and then filtered. The filtrate was analysed for calcium using atomic absorption spectroscopy. From the standard curve it was found that the reading for the analysed sample was 24mg/litre. Calculate the concentration of calcium in the powder (mg/kg).

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

Chapter1: Introduction

Section: Chapter Questions

Problem 1.9QAP

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