You can make saline (salt) or lye (NaOH) solutions. So first you will have to arrange these things to do it which are 2 500ml bottles, 1/2 LB table salt, measuring cup, kitchen scale (optional) and pan for heating. Now first heat the 500-700 ml water in about 100 degrees temperature. Now you have to add the salt in the water and stir it until the salt fully dissolved. Now when its done and cools to room temperature, you need to pour it into the bottle and name that bottle as master solution or saturated solution. Now to make 10% of solution, you will need only 1 part saturated solution to the 9 parts of water. So measure and pour 50ml master solution into second bottle and add 450ml of water, it will be 1:9 ratio or a 10% solution. Now name it as 10% saline. You can recover the excess salt by pouring it on cookie sheet and dry it at room temperature.
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