52 LABOEATOEY MANUAL 



kept under water and cut under water. It must not 

 be allowed to come in contact with the bare skin.) 



With the forceps place a small piece of yellow phos- 

 phorus in the .evaporating dish, which has been filled 

 with water. Cut off a piece with the knife. Does it cut 

 easily? What is the appearance of the new cut sur- 

 face ? What is the consistency of phosphorus ? Pick up 

 a small piece with the forceps and hold it in the air a 

 moment. What takes place? Does phosphorus give 

 off an odor in burning? Why is it kept under water? 

 Rub phosphorus on a piece of filter paper and examine 

 the paper in the dark room. What do you see? Will 

 phosphorus burn at a low temperature? 



Place a small piece of freshly cut phosphorus in a 

 dish of water exposed to the light. Cover with a bell 

 jar and leave for at least 48 hours. Does any change 

 in color occur ? Examine a small quantity of red phos- 

 phorus. Compare in all details its properties with 

 those of yellow phosphorus. What is the difference 

 between an ordinary and a safety match? 



Exercise 29. Sulphur. 



Object: To determine some of the properties of 

 sulphur. 



Apparatus 



Flowers of sulphur Beaker 



Deflagrating spoons Silver spoon 



Eoll sulphur Bunsen burner 



Test tube Test tube holder 



Directions : Examine a little of the flowers of sul- 



