Rech Chemical talks about the water-solubility test of zinc sulfate

Because of long-term engaging in zinc sulfate, ferrous sulfate, manganese sulfate, magnesium sulfate and other products, which are widely used in water soluble fertilizer trace element fertilizer, Rech Chemical are always consulted the question that how to know the water-solubility offertilizer grade zinc sulfate? 

In previous shared articles, Rech Chemical Co. Ltd has refers that the water-solubility involved with insoluble matter. We also often meet overseas customers with the occasions that they wanna do water solubility test by fertilizer grade zinc sulfate samples we send. Hereby, Rech Chemical provides a common international approach to test insoluble matter of  inorganic compounds (GB/ t9738-2008).The methods are as follows:

1. Dissolve the sample in water

2. Filter out the insoluble substances

3. Wash the filter residue with water to completely separate it from the sample 

4. After drying, weigh the insoluble with a balance

5. Use the formula and calculate the mass fraction of the water insoluble substance 

W=(m2-m1)/m×100 (m2 is the mass of filter residue and glass filter, m2 is the mass of glass filter, and m is the mass of sample, all in grams). 

It is worth Rech Chemical Co. Ltd reminding the customers who do this water-solubility test, that in the test, there are corresponding requirements for water, which need to meet the standard of GB/T6682 Level 3 water. In addition, Rech Chemical Co. Ltd’s technician also reminds the tester should try to control the PH value of aqueous solution under 6. If not, zinc sulfate does not dissolve well in water with a PH of 7.5 or above. Therefore, when detecting the water-solubility of zinc sulfate, acid substances should be appropriately added in the solution. The water-solubility of zinc sulfate shows very obviously in acidic solutions.