OF NICKEL. 335 



4. Phosphate of nickel. This salt was ob- Phosphate, 

 tained by mixing together solutions of sulphate 

 of nickel and phosphate of soda in the atomic 

 proportions. The phosphate of nickel imme- 

 diately falls in the state of a green light powder. 

 When dried on the filter, after having been well 

 washed, it has a light pea green colour ; is taste- 

 less, but adheres to the tongue ; and is insoluble 

 in water. 11*375 grains of it, exposed to a red 

 heat, lost 3 '375 grains of their weight. Hence, 

 the constituents of this salt are 



1 atom phosphoric acid 3-5 



1 atom protoxide of nickel 4-25 

 3 atoms water . . 3-373 



11-125 



5. Arseniate of nickel. This salt may be ob- 

 tained by mixing together solutions of sulphate 

 of nickel and arseniate of soda in the atomic 

 proportions. The arseniate, while moist, has a 

 light green colour ; but, when the salt is dried 

 upon the filter, the colour deepens into a dark 

 leek green. It is tasteless, and insoluble in 

 water; yet it slightly reddens vegetable blues. 

 When heated on the sand bath in a temperature 

 of about 500, it gives out two-thirds of its wa- 

 ter, and becomes dark brownish yellow. In a 

 red heat it loses the whole of its water, and be- 

 comes dark brown. Its constituents are 



