How To Make Artificial Sea Water

If laboratories had a staple food, it would be Artificial Sea Water. Scientific studies consume it day after day, milliliter after milliliter (which is a lot when you're mostly working in micro-liters).

Ingredients:

• 1 Liter of MilliQ Water (super-purified, de-ionized H2O)
• NaCl (Sodium Chloride): 23.39 grams
• KCl (Potassium Chloride): .715 grams
• MgCl2 (Magnesium Chloride): 10.633 grams
• CaCl2 (Calcium Chloride): 1.455 grams
• Na2SO4 (Sodium Sulfate): 3.934508 grams
• Tris Base: 2.4228 grams

We have to put all of these in water to make imitation-ocean;
more goes into nature than a lot of laymen think.

Measurements such as these require carefully weighing the mass of the different components on a precision scale that can measure up to the ten-thousands decimal place. Once everything is measured perfectly (or approximately), then it can be mixed in a plastic jar with a magnetic stirrer. An oblong-shaped magnet is placed in the bottom of the plastic jar and the jar is then placed on a magnetic plate stirrer (in this case a Fisher Scientific Thermix Stirring Hot Plate Model 210T), which causes the magnet to rotate very quickly and cause a little whirlpool in the solution. Since this is hard to show in the rather opaque jars I am using, below is a picture of the stirrer in action what is most likely one of Zach's buffer solutions. After 15 minutes to a half an hour, all the components should be solubilized in the water.

The Fisher Scientific Thermix Stirring Hot Plate Model 210T in action!

At this point, the pH level of the mixture needs to be adjusted to match the slightly more basic level of natural sea water, which lies within the range of approximately 8.1 to 8.2. This is done by first calibrating the electrode of a pH meter in pH 4, pH 10, and then pH 7 buffers. Then, simply test the pH of your ASW solution and add super-concentrated acidic to bring down the pH level, or add ... to bring the pH up.

Once that's all done, make sure to label the bottle with a piece of tape and sharpie stating what it is, when it was made, who by, and what the pH level is. Then, you're all set until you find out you have to make more two days later because somebody's experiment called for exorbitant amounts of Artificial Sea Water. Alas, such is life in the lab.

My lab book notes