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Key Concepts:

• Chemical Indicator
• Red Cabbage Juice
• Phenolphthalein
• Acid
• pH Color Change

Demonstration Overview The video presents a concise chemistry demonstration focused on the properties of chemical indicators. The speaker introduces two specific indicators: red cabbage juice and phenolphthalein. These substances are then added to a solution, and the subsequent rapid color changes are observed and highlighted.

Red Cabbage Juice as an Indicator Red cabbage juice, identified as a natural indicator, is introduced into a solution. Upon its addition, the solution undergoes a series of "absolutely amazing" color transformations. Initially, the solution appears purple, then quickly transitions to green, and finally settles on a yellow hue. This sequence of color changes is explicitly attributed to the solution becoming an acid, signifying a shift in its pH level. The speaker emphasizes that these visual changes occur "all thanks to red cabbage juice."

Phenolphthalein Indicator Simultaneously, the demonstration features phenolphthalein, a common synthetic chemical indicator. When phenolphthalein is added, an existing pink color within the solution is observed to "magically disappear." This change indicates that the solution, which was likely initially basic (where phenolphthalein is typically pink), has now become acidic (where phenolphthalein is colorless).

Chemical Explanation and Observations The observed color changes in both indicators are directly linked to a chemical transformation within the solution. The presence of bubbling suggests an ongoing chemical reaction, which results in the solution becoming an acid. This change in acidity is the underlying cause for the distinct color shifts seen with both the red cabbage juice (purple to green to yellow) and the phenolphthalein (pink to colorless). The speaker advises viewers to closely observe the demonstration, stating, "You don't want to take your eyes off of them because you start to see some color changes that were that are there as it starts to bubble away."

Conclusion The demonstration effectively illustrates the utility of chemical indicators in visualizing pH changes. The rapid and distinct color transformations observed with red cabbage juice (from purple to green to yellow) and the disappearance of the pink color with phenolphthalein clearly demonstrate the solution's transition to an acidic state. This highlights how indicators serve as powerful tools for visually representing fundamental chemical reactions and shifts in acidity.