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.
Answer 1 To balance an equation means that there are the same number of each element on each side. The reason a subscript cannot change is that it represents the amount of an â¦ element within a certain compound in relation to any other elements. If that ratio changes, it is no longer the same compound.