If carbohydrate is present, a violet ring will form at the junction of the liquids.

如果存在碳水化合物，在液面交接处就有紫色环生成。

youdao

If carbohydrate is present, a violet ring will form at the junction of the liquids.

如果存在碳水化合物，在液面交接处就有紫色环生成。

youdao