CHEMISTRY OF COMMON THINGS 



Bases in dilute form have a bitter taste and some 

 (potash lye and soda lye) have a soapy, slimy feeling. 

 Bases will turn red litmus paper blue. If blue litmus 

 paper is dipped in acid it will become red. This red 

 litmus paper, if placed in a base solution, will turn blue. 

 Bases will turn colorless phenolphthalein 1 red and acids 

 will make the red disappear. This is a very delicate test 

 for a base. Acids and bases react on each other in such 

 a way that the one undoes the work of the other. 



13. Neutral Substances. Neutral substances are 

 formed by the interaction of a base and an acid. For 

 instance, when the proper proportions of hydrochloric 

 acid (HC1) and caustic soda (NaOH) are poured together 

 in a vessel, two new substances will be formed and both 

 of them will be neutral. The two 

 new compounds thus formed are 

 water (H 2 O) and common table 

 salt (NaCl). The common salt 

 will of course be dissolved in the 

 water, but can be 

 made to crystallize 

 if the solution is 

 heated so that the 

 water evaporates. 

 The way to make 

 a neutral solution 

 by mixing a base 

 and an acid is as 

 follows: Put into 

 a test tube or other vessel a small quantity of 

 an acid and then place in it a small piece of litmus 

 paper and note the color. Now slowly pour in a base 



1 See Glossary. 



FORMING A NEUTRAL SUBSTANCE 

 By mixing a base and an acid. 



