How do you judge whether NaH dispersion(60%) is moisturized or not?
To the best of my knowledge, skyblue color is its standard color and white color implies that it's moisturized or decomposed.
But I'm not sure of this because I was just taught in that way from my seniors and couldn't find any reliable references for this.
Or can anyone help me to titrate or quantify the purity of the compound?
Thanks in advance!
NaH dispersion is grey in color. As it reacts with moisture it become some white. Rough but fast estimation you can get in reaction with EtOH - by quantity of evolved H2
@Andrei Rogoza
Hmmm, is it just grey or little bluish grey? Because I'm used to sky blue color for a very long time... maybe NaH dispersions I used were all partially decomposed until today...
Blue color appear maybe of metalic Na impurities. I have such blue color in some granules of LiH , but most of this are colorless (transparent) .
Fresh opened NaH from Aldrich and Fluka was anytime in grey color.
It's grey, and if it turns white, then it is already hydrolyzed. Rough estimation: react with ethanol (quick) or isopropnaol (more slowly reaction) and collect the evolving hydrogen (be aware, some of the hydrogen gas will dissolve in water). Better: Titration: http://pubs.acs.org/doi/pdf/10.1021/ol0506011
you can take smal amaount and weight it than pour certain amount of water and it turns to NaOH and you can titrated with adjusted HCl presence of an appropriate inicator. (be carefull when pour the NaH into to water due to vigrous reactin. For this reason you should use very little amount of NaH (60%)
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