Química. Proyecto de Ciencias Detectar CO2 con Rojo Fenol.
Experiments with Phenol Red and Bicarbonate of Soda
Introduction to the Experiment
- The episode begins by revisiting phenol red and its application in science fair projects, particularly through a series of chemical experiments.
- Water is mixed with phenol red, which turns slightly acidic due to CO2 from the atmosphere, setting the stage for further experimentation.
Reaction with Bicarbonate of Soda
- A small amount of bicarbonate of soda is added to the acidic solution; however, it only shifts the color to a pinkish hue rather than achieving violet. This indicates that bicarbonate is not sufficiently basic.
- The speaker suggests heating bicarbonate of soda to decompose it into sodium carbonate, which is more basic and will yield better results in changing the color of phenol red.
Observations on Solubility and Color Change
- Sodium carbonate formed from heated bicarbonate is less soluble in water but significantly alters the color of phenol red compared to bicarbonate alone. This demonstrates practical applications in chemistry experiments.
- A visual comparison between solutions shows a marked difference in coloration when using sodium carbonate versus bicarbonate, emphasizing the importance of solubility in chemical reactions.
Acidification Process Demonstration
- The experiment continues by adding CO2 directly into water containing phenol red using a bottle setup, illustrating how increased atmospheric CO2 leads to ocean acidification affecting marine life like corals and mollusks.
Alternative Methods for Generating CO2
- If participants lack access to bottled CO2, they can create it using vinegar (cleaning vinegar recommended) mixed with baking soda while controlling effervescence to prevent overflow during reaction. This method effectively generates CO2 gas for experimentation purposes.
Final Experiment Setup
- An alternative setup involves using a container with holes for tubing where baking soda and vinegar are combined; this allows for controlled release of CO2 without needing specialized equipment or materials. It highlights creativity in conducting experiments at home or school settings.
Conclusion
- The episode wraps up by encouraging viewers about experimenting with simple household items while reinforcing concepts learned throughout the session regarding acidity, basicity, and their effects on indicators like phenol red.