Carbonated water works by dissolving carbon dioxide gas into water under specific conditions.
Sparkling water is created when a combination of high gas pressure and low temperature causes carbon dioxide to dissolve in water, forming carbonic acid. This is the fundamental process behind carbonation. The CO₂ molecules bond with the water molecules under these conditions.
The Science Behind the Bubbles
The magic of carbonated water lies in the solubility of carbon dioxide gas in water.
Key Factors for Carbonation
According to the provided information, two main factors are crucial for dissolving CO₂ in water:
- High Gas Pressure: Increasing the pressure above the water surface forces more gas molecules into the liquid. Think of it like pushing more CO₂ into the water.
- Low Temperature: Gases are more soluble in cold liquids than in warm ones. Keeping the water chilled helps it hold onto the dissolved CO₂.
When these conditions are met, carbon (from CO₂) dissolves in water, creating carbonic acid ($H_2CO_3$). This weak acid is what gives carbonated water its slightly tangy or biting taste.
Why Bubbles Appear
The dissolved carbon dioxide remains in solution as long as the high pressure and low temperature are maintained (like when a bottle is sealed and chilled). However, when conditions change, the CO₂ comes out of solution:
- Reduced Pressure: Opening a bottle or can releases the pressure above the liquid.
- Increased Temperature: Warming the liquid makes CO₂ less soluble.
When the temperature is raised, or the pressure is reduced, carbon dioxide escapes from the water in the form of bubbles. These bubbles are the CO₂ gas returning to its gaseous state and rising to the surface. The fizz you see and hear is this process in action.
Summary of the Process
Here's a simple breakdown:
- Conditioning: Water is chilled to a low temperature.
- Infusion: Carbon dioxide gas is forced into the water under high pressure.
- Dissolving: The CO₂ dissolves in the water, forming carbonic acid.
- Stabilization: The carbonated water remains stable as long as it's sealed and cold.
- Release: When the seal is broken or the water warms, pressure decreases, and temperature may rise.
- Effervescence: Dissolved CO₂ escapes as bubbles (fizz).
This simple but effective process is used to make everything from sparkling water and soda to other carbonated beverages.
