26 FIRST YEAR COURSE IN GENERAL SCIENCE 



DIRECTIONS FOR WORK: 



(1) Pour 25 cu. cm. of water into an evaporating dish and 

 add a few drops of an acid. Place the three litmus papers 

 on a clean paper. With a clean rod, put a drop of acid on 

 one end of each paper. Record any or no change of color 

 observed, in the table below. 



(2) Wash the dish and rod clean and dry them. Pour 

 25 cu. cm. of water into a dish and add a few drops of am- 

 monium hydroxide (ammonia solution). Put a drop on 

 each paper where it will not touch the spot made in Case 1. 

 Record change in the table below. 



(3) Make the apparatus clean and repeat the above tests 

 with a solution of common salt, a neutral substance. 



(4) Take home 2 sq. in. of lilac paper (provided by the 

 teacher) and test as many other solutions as possible. 



Litmus papers Blue Pink Lilac 



Acid Solution 



Basic 



Neutral " 



Soap 



Molasses ' 



Vinegar " ....'. 



Milk (sweet) 



" (sour) 



Sugar solution 



Starch " 



Baking soda " 



RESULTS 



1. Describe the behavior of each of the three litmus 

 papers with each of the first three solutions. 



2. Which is the best paper to use if only one can be had? 

 Why? 



