From: poutnik4nntp@gmail.com   
      
   Dne 11/02/2017 v 17:30 asaminu91@gmail.com napsal(a):   
      
   > How much water do I need   
      
   Hmm, it is quite a sloppy question.   
   Do not expect satisfying answers   
   when your are not particular in questions.   
      
   BTW, it looks like a fast call for the homework answer.   
      
   Get the concentration of HCl  c0, probably 35-38 % - see the bottle   
   Get its density ro, probably about 1.2, see the bottle   
   Get the target concentration  c %   
      
   Use the  cross rule, valid for masses   
      
   c0       c   
     \   /   
       c   
     /   \   
   0       c0 - c   
      
      
   in mass :take c grams of HCl and c0 - c grams of water   
   in volume : take c / ro ml of HCl ad c0 - c ml of water   
      
   Multiple both volumes to get final volume V   
      
   HCl  :  c / ro * V / [ c/ro + c0 - c ]   
   Water:  ( c0 - c ) * V / [ c/ro + c0 - c ]   
      
   --   
   Poutnik ( The Pilgrim, Der Wanderer )   
      
   A wise man guards words he says,   
   as they say about him more,   
   than he says about the subject.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)