Below is a list of chemical grades in order of purity, from highest to lowest.
Highest quality; often equals or exceeds the latest purity standards set by the American Chemical Society (ACS). This is the only universally accepted standard. Chemicals are of the highest purity attainable.
Purity is generally equal to ACS grade. This grade is suitable for analytical work and is more than adequate for general lab use.
A grade of sufficient purity to pass certain tests prescribed by the US Pharmacopoeia (USP); acceptable for drug use. USP grade may be used for most laboratory purposes.
A grade of sufficient purity to meet the standards of the National Formulary (NF).
An upper-level intermediate quality. Exact impurities may not be known; however, lab grade is usually pure enough for most educational laboratories.
Purified, pure, or practical grade; a lower-level intermediate quality. Although this grade does contain impurities, it is usually pure enough for use in educational laboratories.
A good-quality grade used industrially. Use caution when substituting for reagent-grade or lab-grade chemicals.
When making a solution, one must first decide what degree of chemical purity is needed. Many types of chemicals are available in several grades of purity. Most of the chemicals listed in our catalog belong to one of the following 3 categories, in order from least pure to most pure.
Choose the most appropriate grade based on need and cost. Lab-grade chemicals, because of their low cost and good chemical purity, find wide use in educational applications, such as teaching laboratories at both the secondary school and college levels. Reagent-grade chemicals are typically ACS-grade chemicals that have been repackaged and have therefore lost their ACS certification.
Carolina also offers a choice of packaging for a limited number of chemicals. Corrosive chemicals, such as concentrated acids, are normally packaged in glass bottles. For safety and convenience, our customers may order these chemicals packaged in plastic-coated safety bottles. A plastic-coated safety bottle will not shatter when dropped, which helps to contain the spill and simplify cleanup. Look at the item descriptions in the chemical section of the catalog for those chemicals available in plastic-coated safety bottles.
For safety purposes, read a chemical’s label twice before use. Read the label first when you take the chemical off the shelf and again before you remove any chemical from the bottle. When preparing solutions using concentrated chemicals, slowly add the more concentrated solution (e.g., sulfuric acid) to the less concentrated one (e.g., water). The reverse procedure can cause the solution to boil and spatter.
Lab Safety Equipment from Carolina
Carolina offers an extensive line of chemicals, chemistry sets, lab safety products and equipment.