CHAPTER V 



THE CHEMISTRY OF THE PLANT 



In these paragraphs are brought together the com- 

 moner plant constituents and products, giving the name, 

 chemical formula and occurrence of each, so far as these 

 are known. 



Substance and Formula 



Water 

 H2O 

 Inorganic Acids and Salts 



Sulphuric 



H,S04 

 Nitric 



HXO3 

 Hydrochloric 



HCl 



Phosphoric 

 H3PO4 (and 



other forniy) 



Occurrence 



In all parts of the plant; the 

 chief solvent. 



These acids are present almost 

 exclusively as the neutral or 

 acid salts of various metals, 

 especially Ca, K, Na and Mg. 

 They are largely absorbed by 

 the plant from the surround- 

 ing water in the forms in which 

 they are present in the plant, 

 or a shifting of the bases oc- 

 curs after their absorption. 

 Chiefly as the Ca salt in some 

 crystals. 

 As various salts in the cell sap. 



Chiefly as K or Na salts in the 

 cell sap of plants, especially 

 those of salty soil, or in ma- 

 rine algae. 



In the cell sap as Ca, Na or K 

 salts. 



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