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Synthesis of Azo Dyes

Home
Introduction
Part I
Part II
Part III
Clean Up
Conclusion

Synthesis of Azo Dyes

Home
Introduction
Part I
Part II
Part III
Clean Up
Conclusion
More

Part I

Add NaCl to your reaction mixture, heat it, and then cool it again.

mass of NaCl used

The photo shows a piece of weighing paper on top of a laboratory scale. If there is anything in top of the weighing paper, it is similar enough in color that it is not visible to the eye. The screen of the scale reads “0.493 g.” Next to the scale, a gloved hand holds a small brown glass reagent bottle labeled “Sodium Chloride.”

adding to dye solution

The video shows a small Erlenmeyer flask clamped in place in a sand bath. There is a boiling stick in the flask, as well as a small quantity of dark red solution. The upper walls of the flask are covered in condensation, indicating heating. Also in the sand bath is a metal temperature probe. A gloved hand pours the contents of a diagonally folded piece of weighing paper into the flask. We see these contents to be clear, whitish crystals. The boiling stick is used to stir the mixture, which has turned a lighter orange color, covered by yellow-orange bubbles on the surface. The screen goes black except for a caption that reads: “Once dissolved, cool to room T and then on ice.” When the video returns, we see the Erlenmeyer flask immersed in a large plastic tub filled with ice. The flask contains the boiling stick and some mostly unseen brownish orange substance.

Cool and analyze the product.

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