The Complex-Dilution Method

Silver phosphate (Ag3P04) has also been grown in silica gel41 (0.5 Msodium metasilicate plus 1 M acetic acid). The experiments are performed at room temperature, in the dark, using test tubes. The solution above the gel contains Ag3P04 and nitric acid which is added to keep the phosphate in solution. As 

Small crystals or dendrites of metals can be formed in a similar way by reducing a metal salt contained in a gel. Lead dendrites are formed rapidly when metallic zinc is used as the reducing agent.41 43 Similarly, small copper tetra-hedra1 and gold platelets3,44 can be formed by reduction in gels. 

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Three types of reactions that have been performed in gels are covered in the following sections (1) standard growth, (2) the complex dilution method, and (3) reduction to form metallic crystals or dendrites. 

B. COPPER (I) CHLORIDE CRYSTALS GROWN BY THE COMPLEX DILUTION METHOD... 

Copper(I) chloride is precipitated from a concentrated solution of HC1 by dilution during the diffusion process. This process is illustrative of the complex dilution method of growing crystals. 

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