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Question

Posted on: March 6 2013

Following preparation gives problems: Burow water 90 g zinc sulfate 4 G chlorbutol 10 g Aqua AD 500 ml

We first dissolved the chlorbutol in hot water and then ZnSO4 added and dissolved. After adding Burow water we obtain a fairly stable milky suspension. But when cooling out crystallization of probably the chlorbutol? If we first dissolve the chlorbutol in a minimal amount of alcohol we also obtain a clear solution, but adding water causes re-crystallization.

Answer

The water solubility of Chlorbutol is 1 in 130 which means you need 1300 ml of water to dissolve 10 g. You are not yet half.

a first possible solution for a clear solution is to dissolve 3.8 g of chlorbutol in 500 ml of water. Then the solution is saturated. A commonly used concentration is 0.5%; You are then slightly above it.
If you want to solve the 10 g then you will apparently need much more as a minimal amount of alcohol. The solubility in alcohol is 1 in 0.6 so you need 10 g 6 ml But then we work in the absence of water.
one could try the following on one tenth of the total quantity. Take 7.5 ml of alcohol (15%) and dissolve on 1 G chlorbutol and dilute very gradually with water. In the occurrence of a cloudy add 1 ml of alcohol and dilute again with water etc... Up to 50 ml. Note how much alcohol was added. Multiplied this quantity by 10 and you will then know the amount of alcohol we need to add for 500 ml solution. I hope ZnSO4 and Burow's solubility will not be ï Nvloeden???

there is another possibility and this is solubilizing but also this is not easy and requires a lot of testing! And then we are with a lot of surfactant in the solution. Should also be discussed with the doctor.