Preparing Standard Solutions in the Lab

Standard solutions are prepared to have a precisely known concentration or composition. In analytical chemistry, this accuracy is important because it supports reliable results. A primary standard is a highly pure, stable substance with a high molar mass. It is fully soluble in water, which is the most commonly used solvent ...

标准溶液是具有准确已知物质量的溶液。它由一级标准品制备，一级标准品是一种高纯度、高摩尔质量、亲水性和稳定的物质。

制备包括在称量船中准确称量适量的一级标准品，并使用漏斗将其转移到容量瓶中。对空称量船进行重新称重，以检查是否有任何剩余的固体物质。

加入少量蒸馏水，将漏斗中的固体冲入培养瓶中。旋转容量瓶以完全溶解固体。添加更多的水，直到其水位接近校准标记。此时，移液水以将溶液浓度精确提高到校准标记。

将培养瓶关闭并倒置数次，以确保完全混合。在培养瓶上标记化学成分、浓度和制备日期。

该一级标准溶液用于标准化二级标准品 – 纯度较低且稳定性较差的物质。