. Elementary chemical microscopy . Eig. 146. Decanting a Drop of Liquid from a Precipitate. When the clear decanted liquid is not wanted for analysis and only the sediment, or precipitate, in the original drop is to be utilized, the decanted portion and connecting stream are both wiped off the slide with filter paper while the slide is inclined and the preparation heated gently below the wiped-off drop to pre- vent any farther spreading. In cases where the sediment in the drop persists in flowing with the liquid being drawn off, and where heating is not objection- able, the slide is tipped so
. Elementary chemical microscopy . Eig. 146. Decanting a Drop of Liquid from a Precipitate. When the clear decanted liquid is not wanted for analysis and only the sediment, or precipitate, in the original drop is to be utilized, the decanted portion and connecting stream are both wiped off the slide with filter paper while the slide is inclined and the preparation heated gently below the wiped-off drop to pre- vent any farther spreading. In cases where the sediment in the drop persists in flowing with the liquid being drawn off, and where heating is not objection- able, the slide is tipped so as to cause all the liquid to again flow back into the original source and the drop is evaporated to dry- ness at a low temperature, exceptional care being taken to pre- vent heating the residue after evaporation. This step will usually cause the sediment to cling to the glass and to aggluti- nate. A drop of water or the proper liquid is then carefully added, the preparation allowed to stand a few seconds to permit the soluble compounds to pass into solution and the solution then decanted as above described. Usually a clear liquid may now be obtained without difficulty.
Size: 1850px × 2701px
Photo credit: © The Bookworm Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, booksubjectmicroscopy, bookyear1
