1. Effervescence (Bubbling): The most obvious and immediate sign is the production of bubbles. This is due to the release of carbon dioxide gas (CO2):
```
NaHCO3(aq) + HCl(aq) → NaCl(aq) + H2O(l) + CO2(g)
```
2. Possible Color Change: The solution might change color depending on the initial color of the extract and the color of the resulting solution. For example:
* If the extract was initially basic (from the NaHCO3) and contained a compound that changes color with pH, the solution might become more acidic, causing a color change.
Important Note: It's crucial to be careful when handling acids, as they can be corrosive. Always wear appropriate safety gear and work in a well-ventilated area.
