P5.3—Standard laboratory practice in plans

Standard quantitative practice reduces avoidable variation: prepare standard solutions accurately, weigh by difference, obtain concordant titres, heat to constant mass and take extra readings near an inflection point.

Each technique solves a different problem. Weighing by difference limits transfer error; constant mass confirms completion; extra points around a sharp change locate an endpoint or transition.

A titration uses a rough titre to locate the endpoint, then concordant titres within the stated tolerance; a gravimetric experiment reheats and reweighs until the mass is constant.

Repeating an inconsistent technique does not create concordance; the method and acceptance criterion must be applied.