THE PROPERTIES OF COLLOIDS 



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their insolubility in water. As Over ton has pointed out, the power of 

 amorphous carbohydrates to take up fluids is modified by alteration of their 

 chemical structure in the same direction as the solubility of the corresponding 

 crystalline carbohydrates. Thus, if the hydroxyl groups in the sugars be 

 replaced by nitro, acetyl, or benzoyl groups, they become less soluble in 

 water, while their solubility in alcohol, acetone, &c., is increased. In the 

 same way the replacement of the hydroxyl groups in cellulose by N0 2 groups 

 diminishes the power possessed by this substance of taking up water, but 

 renders it capable of swelling up or dissolving in alcohol and acetone. 



