2) Element symbol: P
 

3) Number of electrons, protons, and neutrons: 15 electron, 15 proton, 16 neutrons
 

4) Atomic number: 15
 

5) Atomic mass: 30.97376
 

6) Characteristics:

Ordinary phosphorus is white, but turns light yellow when exposed to sunlight. It is a crystalline, translucent, waxy solid, which glows faintly in moist air and is extremely poisonous.
 

7)

History:

Phosphorus was discovered about 1669 by the German alchemist Hennig Brand (flourished 1670) in the course of experiments in witch he attempted to prepare gold from silver.

Three things made from the element:

Phosphorus compounds are used in

- clarifying sugar solutions

- weighing silk

- fireproofing as in such alloys as phosphor bronze and phosphor copper
 

8) Isotopes:

All naturally occurring phosphorus is the stable isotope, phosphorus-31. Radioactive phosphorus-32 has a half-life of 14.3 days; it is a useful tracer in studies of the life cycles of plants and animals.
 

9) Phosphorus combines readily with oxygen to form oxides, of which the most important are phosphorus oxide and phosphoric oxide.

Phosphorus forms hydrides with hydrogen.

All of the halogens combine directly with phosphorus to form halides.
 

10) Phosphorus melts at 44.1 °C (111.4 °F) and boils at 280 °C (536 °F).