Precautions When Using Qualitative and Quantitative Filter Paper
Note on the filter paper box that when using the quantitative and qualitative analysis filter paper to filter the precipitate:
1. Generally uses natural filtration, using the filter paper body and the ability to retain solid particles to separate the liquid and solid;
2. Because the mechanical strength and toughness of the filter paper are small, try to use less filtration to filter. If the filtration speed must be increased, the filtration failure will be prevented to prevent the filtration. When the air pump is filtered, it can be stacked in the funnel according to the pumping force. Put 2 to 3 layers of filter paper, when vacuum filtration, put a layer of dense filter cloth on the funnel, and then filter the filter paper;
3. It is best not to filter hot concentrated sulfuric acid or nitric acid on the filter paper;
The difference between the use of quantitative filter paper and qualitative filter paper is that qualitative filter paper is used for qualitative chemical analysis and corresponding filtration separation; quantitative filter paper is used for gravimetric analysis test and corresponding analytical test in quantitative chemical analysis. The function of the quantitative filter paper is mainly used for the ashing weighing analysis experiment after filtration. The ash weight of each filter paper after ashing is a fixed value, and the qualitative filter paper is used for general filtration.
In addition, under what circumstances are the quick filter paper, medium speed filter paper and slow filter paper used separately? The main components are fibers, namely C, H, O, and a small amount of other elements. However, the ash produced by the quantitative filter paper is seldom, negligible, and is used for quantitative filter paper and qualitative filter paper.