Permanent volumetric change

Volumetric analysis involves using a solution of accurately known concentration, a standard solution, in a quantitative reaction to determine the concentration of the other reactant. The procedure is known as titration. One solution is measured quantitatively into a conical flask using a pipette. The other solution is dispensed from a burette until a permanent colour change appears in the solution in the conical flask. 

Low permanent linear and volumetric changes are generally desirable, as they indicate good material stability and minimize shrinkage to prevent loosening of a refractory lining in service. Also, ingress of corrosive material behind the hot face is prevented. 

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