Jump to content

  • Log in with Facebook Log in with Twitter Log in with Windows Live Log In with Google      Sign In   
  • Create Account

Submit your paper to J Biol Methods today!
Photo

5 M NaCl stock

stocks solubility NaCl

  • Please log in to reply
5 replies to this topic

#1 El Crazy Xabi

El Crazy Xabi

    Veteran

  • Active Members
  • PipPipPipPipPipPipPipPipPipPip
  • 199 posts
20
Excellent

Posted 29 October 2012 - 02:04 PM

Hi guys,

I was trying to make a 5 M NaCl stock but I have problems to dissolve it.

I added 292.2 g to about 750 mL MQ initially but after 2 hours didn't dissolve so I added more water and heat it up. I even reach to boiling to dissolve but did't work either. Even worse, the solution surface started to cristalize ¬¬'...
It's the first time I have to prepare this stock and I'm a little bit paranoid alreadyPosted Image , maybe the balance I used does not work properly or the bottle had another chemicalPosted Image ?

I don't know, having a problem with this and not with other really complex solutions pfff

If anybody has any suggestion trick or whatever, it would be good

#2 bob1

bob1

    Thelymitra pulchella

  • Global Moderators
  • PipPipPipPipPipPipPipPipPipPip
  • 5,826 posts
413
Excellent

Posted 29 October 2012 - 02:56 PM

The solubility of NaCl in H20 is about 360 g/l - you have 750 ml of water (therefore 360*0.75=270) and 292 g...add some more water.

#3 El Crazy Xabi

El Crazy Xabi

    Veteran

  • Active Members
  • PipPipPipPipPipPipPipPipPipPip
  • 199 posts
20
Excellent

Posted 29 October 2012 - 03:56 PM

I added more than the expected and it didn't dissolve overnight

#4 bob1

bob1

    Thelymitra pulchella

  • Global Moderators
  • PipPipPipPipPipPipPipPipPipPip
  • 5,826 posts
413
Excellent

Posted 30 October 2012 - 02:11 AM

I would try re-weighing the NaCl. It does tend to crystallize at the surface - keep it covered with parafilm. I can't recall ever having it not dissolve, so I'm not much help unfortunately.

#5 hobglobin

hobglobin

    Growing old is mandatory, growing up is optional...

  • Global Moderators
  • PipPipPipPipPipPipPipPipPipPip
  • 5,545 posts
104
Excellent

Posted 30 October 2012 - 09:34 AM

Do you need 5 M exactly or should it just be a saturated NaCl solution? If it's the latter case, then some precipitation is part of it (it's an equilibrium of precipitation and dissolving again...)
And add the NaCl slowly and not all at once...

One must presume that long and short arguments contribute to the same end. - Epicurus
...except casandra's that belong to the funniest, most interesting and imaginative (or over-imaginative?) ones, I suppose.

That is....if she posts at all.


#6 Ahyi

Ahyi

    member

  • Active Members
  • Pip
  • 16 posts
0
Neutral

Posted 04 November 2014 - 12:06 AM

I found autoclaving helps with dissolution with even just 500ml 5M NaCl solution







Home - About - Terms of Service - Privacy - Contact Us

©1999-2013 Protocol Online, All rights reserved.