CHEMISTRY OF COMMON THINGS 



21 



Great quantities of common salt are used in cooking 

 and preserving meats and other foods, but much more 

 is used in the manufacture of washing soda, soap, glass, 

 bleaching powders, baking powders, baking soda, etc. 

 About 4,000,000 tons are used annually in the United 

 States alone. 



MAKING SALT BY EVAPORATION IN CALIFORNIA 



QUESTIONS AND EXERCISES 



1. Your mother hangs wet clothing on the line to dry. Where 

 does the water go? What becomes of sweat on your body? 



2. Test with litmus paper the compounds which you have at 

 home. (Dry substances must be dissolved in water. Test the 

 water before using to see if it affects the litmus.) Make a list of 

 them as follows: 



1 Neutral salts do not affect red or blue litmus. 



