Answer:
Meant to be used in both the teaching and research laboratory, this calculator (see below) can be utilized to perform a number of different calculations for preparing percent (%) solutions when starting with the solid or liquid material. It is very common to express the concentration of solutions in terms of percentages. Percent means per 100 parts, where for solutions, part refers to a measure of mass (μg, mg, g, kg, etc.) or volume (μL, mL, L, etc.). In percent solutions, the amount (weight or volume) of a solute is expressed as a percentage of the total solution weight or volume. Percent solutions can take the form of weight/volume % (wt/vol % or w/v %), weight/weight % (wt/wt % or w/w %), or volume/volume % (vol/vol % or v/v %). In each case, the percentage concentration is calculated as the fraction of the weight or volume of the solute related to the total weight or volume of the solution.
Because percent solutions can be expressed in three different ways, it is imperative that the type of percent solution be explicitly stated. If this information is not provided, the end user is left to "guess" whether w/v %, w/w %, or v/v % was used. Each percent solution is appropriate for a number of different applications. For example, commercial aqueous reagents, such as concentrated acids and bases, are typically expressed as weight/weight % solutions. For example, commercially available concentrated hydrochloric acid (HCl) is 37% by weight (w/w %). On the other hand, many dilute solutions used for biological research are expressed as weight/volume % (e.g., 1% sodium dodecyl sulfate, SDS). Volume/volume % solutes are also common, and are used when pure solutes in liquid form are used. For example, a 70 % (v/v) solution of ethanol can be prepared by dissolving 70 mL of 100% (i.e., 200 proof) ethanol in a total solution volume of 100 mL.
Step-by-step explanation: