Security Stud. 1  Full mortise hinges are available with security studs for added safety. 2  With the door in its closed position, a stud attached to one leaf of the hinge projects into a hole in the matching leaf.
Net Ionic Equation. A chemical reaction involves the conversion of reactant atoms or molecules to product. During any chemical reaction, reactant molecules are joined together to form a product which has different chemical and physical properties than the reactants.
Chemical equations must be balanced -- they must have the same number of atoms of each element on both sides of the equation. As a result, the mass of the reactants must be equal to the mass of the products of the reaction.