NaOH 0.1mol standard tube
A standard tube is a tube in which a precise amount of the reagent, either solid or liquid, is already contained. When using a standard tube to prepare a solution, all reagents in the standard tube are transferred to a 1 liter volumetric flask and then water is added to the mark to obtain 1 liter of standard solution with the concentration indicated on the label of the standard tube.
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