Benzoates with the earthy and metallic Salts. 261 



I. The fluid after the precipitation with benzoate o£ 

 ammonia was colourless. 



1. With a few drops of sulphuret of ammonia there oc- 

 curred only a pale yellowish gray, and after 24 hours there 

 was deposited a little dark yellow sulphur. 



2. With caustic aaijnonia in excess, there was no tur- 

 bidity or dulhiess. 



3. With tincture of galls made with alcohol, — at first no 

 alteration, but after several hours a weak grayish colour 

 appeared. 



4. Wiih succinate of ammonia, no alteration. 



5. With prussiate of annnonia, — did not become blue, 

 but only somewhat muddy, and after a long time deposited 

 a pellicle of Prussian blue. 



c. One gramniC of dry benzoateof iron was heated for half 

 an hour, whereby it at first swelled, smoked, burned and 

 charred. A daik-red oxide remained, which dissolved com- 

 pletely in muriatic acidj it weighed full 0*24 of a gramme, 

 agreeing, except a centigramme, with the proportion in the 

 former experiment (a). The difference was owing to a 

 smaller charge of oxygen in the oxide heated to redness 

 along with the acid. 



d. Ten parts (about five grammes) benzoate of iron were 

 mixed with six ounces of water, and placed in a heat of 

 + 17 to 18° for 24 hours; during which the phial was 

 often shaken. Gathered on a clean, dried, and accurately 

 weighed filter, it showed after drying a loss of nearly -rv'b 

 of a gramme. On the evaporation of the water, there re- 

 mained faint traces of red oxide of iron that could not be 

 weighed, besides a small portion of benzoic acid. 



e. Filiy parts of benzoate of iron were boiled one hour 

 with four ounces of water. The salt u as partly unaltered, 

 partly decf)mposed to oxide, and also in |)art dissolved, 

 lioiling water produces therefore a more speedy and more 

 general effect on this benzoate than cold water. 



/'. Benzoate of iron dissolves in moderately strong mu- 

 riatic acid, when agitated. A surplus of acid should there- 

 fore be carefully avoided in all precipitations with ben- 

 zoates. 



S- 25 grammes of benzoate of iron were mixed and 

 agitated in a closed phial with about one ounce of caustic 

 annnonia. Alter renting li? hours on a warm stove, the 

 cle:ir benzoate of ammonia was bv filtering separated I'rom 

 the oxide of iron, which, after being collected and washed 

 on a nicely weighed filter and well dried, weighed 6-50 

 grimmes, which (minus 25 grammes) coincide* with th« 

 K 3 \tX<H' 



