Lab Questions from Lab: Gravimetric Determination of Calcium as CaC2O4•H2O What is the purpose of the methyl red indicator? Why does a color change to yellow tell you that the reaction is complete? Why is the precipitate rinsed with ice-cold water in step 4? Why not room temperature or hot water? Why is it important that the funnels be placed in a desiccator before weighing (steps 1 and 5)?

Lab Questions from Lab: Gravimetric Determination of Calcium as CaC2O4•H2O What is the purpose of the methyl red indicator? Why does a color change to yellow tell you that the reaction is complete? Why is the precipitate rinsed with ice-cold water in step 4? Why not room temperature or hot water? Why is it important that the funnels be placed in a desiccator before weighing (steps 1 and 5)?

Chemistry by OpenStax (2015-05-04)

1st Edition

ISBN:9781938168390

Author:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Publisher:Klaus Theopold, Richard H Langley, Paul Flowers, William R. Robinson, Mark Blaser

Chapter15: Equilibria Of Other Reaction Classes

Section: Chapter Questions

Problem 107E: What mass of NaCN must be added to 1 L of 0.010 M Mg(NO3)2 in order to produce the first trace of...

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