If the pH of the solution is lower than the desired pH, then a strong base (often NaOH) is added to raise the pH.
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: Preparation of Methylene Blue Concentrations via Serial Dilutions.Preparation of Methylene Blue Solutions.Measuring Absorbance of Methylene Blue Working Solutions.Prepare Known Concentrations of Methylene Blue Working Solution via Dilution.Prepare Stock Solution of Methylene Blue.Part II: Preparation of a Standard Curve.Part I: Solution Prep of 30-mLs of 13.6% Sodium Acetate.Solutions with Insoluble Solutes in Cold Water Solutions with Soluble Solute and water as the solvent Activity 1: Calculating the Amount of Solute and Solvent.Key considerations when making solutions:.