An excellent lab to introduce physical and chemical changes. A small tub tint is dropped into a test tube with oil and nothing happens. Water is added to the tube, which displaces the oil and begins to dissolve the tub tint. The tub tint releases a colored dye, citric acid, and sodium bicarbonate. The two chemicals react to produce carbon dioxide gas, which bubbles to the top of the tube, taking colored water droplets with it. The tube can also be capped and gently rocked back and forth to illustrate the difference in density of the two liquids, and can be shaken to demonstrate a mixture.
Demo Pack includes: 1 oz. Vegetable Oil, Preform Tube, Tub Tint 3-pack
Classroom Pack includes: 10 - 1 oz. Vegetable Oil, 10 Preform Tube, 10 Tub Tint 3-pack