Carbon Dioxide
Explanation
The chemical properties of metal hydrogen carbonates (bicarbonates), specifically their reaction with acids. This is a fundamental concept in understanding the behavior of acids, bases, and salts.
Analysis:
- Chemical Composition: Baking soda is chemically known as Sodium Hydrogen Carbonate ($NaHCO_3$). Lemon juice contains Citric Acid ($C_6H_8O_7$).
- Reaction Mechanism: When a metal hydrogen carbonate reacts with an acid, it undergoes a chemical change to produce a corresponding salt, water, and carbon dioxide gas.
- Observation: The "bubbles" are a result of effervescence, which indicates the rapid release of a gas. In this reaction, the gas evolved is Carbon Dioxide ($CO_2$).
- Chemical Equation: The general reaction can be represented as:
$NaHCO_3 \text{ (Baking Soda)} + H^+ \text{ (from Acid)} \rightarrow Na^+ + H_2O + CO_2 \uparrow$
Key Takeaway:
Acids react with metal carbonates and metal hydrogen carbonates to liberate Carbon Dioxide gas, along with the formation of a salt and water.