The term “bring to volume” (btv) or “quantity sufficient” (qs) means adding water to a solution you are preparing until it reaches the desired total volume.Then transfer the solution to a 500 mL graduated cylinder and bring the volume to 500 mL For a 500 mL solution, start by dissolving the solids in about 400 mL deionized water (usually about 75% of the final volume) in a beaker that has a magnetic stir bar.
You may want to wash the stir bar with dishwashing detergent, followed by a complete rinse in deionized water to ensure that the stir bar is clean. Do not handle the magnetic stir bar with your bare hands. If using a magnetic stir bar, be sure that it is clean.For example, if you need to make 50 mL of a solution, it is preferable to use a 50 mL graduate cylinder, but a 100 mL cylinder can be used if necessary. Always use a graduate cylinder to measure out the amount of water for a solution, use the smallest size of graduated cylinder that will accommodate the entire solution.2 H 2O has a MW of 147.0 grams (110.0 g + the weight of two waters, 18.0 grams each).For example, anhydrous CaCl 2 has a MW of 111.0 g, while the dehydrate form, CaCl 2 Be sure to pay attention to which one you are using. Others come as “anhydrous” which means that there is no bound water. Some chemicals come as hydrates, meaning that those compounds contain chemically bound water. Be sure you are using the right form of the chemical for the calculations.Make sure to always research the precautions to use when working with specific chemicals.Key considerations when making solutions:
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