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Reagent Chemicals [a] is a publication of the American Chemical Society (ACS) Committee on Analytical Reagents, [1] detailing standards of purity for over four hundred of the most widely used chemicals in laboratory analyses and chemical research. Chemicals that meet this standard may be sold as "ACS Reagent Grade" materials.
ACS grade is the highest level of purity, and meets the standards set by the American Chemical Society (ACS). The official descriptions of the ACS levels of purity is documented in the Reagent Chemicals publication, issued by the ACS. [3] [4] It is suitable for food and laboratory uses. Reagent grade is almost as stringent as the ACS grade.
Here, a primary standard is typically a reagent which can be weighed easily, and which is so pure that its weight is truly representative of the number of moles of substance contained. Features of a primary standard include: High purity; Stability (low reactivity) Low hygroscopicity (to minimize weight changes due to humidity)
Methanesulfonyl azide melts at 18 °C and decomposes from 120 °C. [1] Like many other azides, it is explosive. [3] At low temperature, methanesulfonyl azide crystallizes in the triclinic crystal system in the space group P1 with the lattice parameters a = 5.6240 Å; b = 5.9498 Å, c = 7.6329 Å, α = 72.216°, β = 70.897°, and γ = 88.601°, and two molecules per unit cell.
Uranyl acetate is also used in a standard test—American Association of State Highway and Transportation Officials (AASHTO) Designation T 299—for alkali-silica reactivity in aggregates (crushed stone or gravel) being considered for use in cement concrete.
In 1874, a group of American chemists gathered at the Joseph Priestley House to mark the 100th anniversary of Priestley's discovery of oxygen.Although there was an American scientific society at that time (the American Association for the Advancement of Science, founded in 1848), the growth of chemistry in the U.S. prompted those assembled to consider founding a new society that would focus ...
One form of this, known as central centrifugal cicatricial alopecia, can be especially painful, Dr. Rodney says. “The hallmark symptoms are burning, soreness, and tenderness of the scalp,” she ...
In chemistry, a reagent (/ r i ˈ eɪ dʒ ən t / ree-AY-jənt) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. [1] The terms reactant and reagent are often used interchangeably, but reactant specifies a substance consumed in the course of a chemical reaction. [ 1 ]