When baking soda is mixed with lemon juice, bubbles are formed with the evolution of a gas. What type of change is it? Explain.

When baking soda, or sodium bicarbonate (NaHCO₃), reacts with lemon juice containing citric acid (H₃C₆H₅O₇), the resulting bubbles and the evolution of gas represent a chemical change. Here’s why:

1. Chemical Change Nature:
– Chemical changes involve the formation of new substances with different properties compared to the original substances. When baking soda and citric acid in lemon juice combine, they undergo a chemical reaction.

2. Reaction Explanation:
– The reaction between baking soda and citric acid generates carbon dioxide gas (CO₂). The chemical equation for this reaction is: NaHCO₃ + H₃C₆H₅O₇ → CO₂ + H₂O + Na₃C₆H₅O₇
– The observed bubbles signify the release of carbon dioxide gas due to this reaction.

3. Chemical Change Characteristics:
– Formation of new substances (such as carbon dioxide, sodium citrate, and water) that differ from the original reactants.
– Emergence of gas bubbles, indicating the evolution of carbon dioxide gas, a product of the chemical reaction.
– Alteration in the chemical composition and properties of the substances involved, showcasing the distinct nature of the resulting compounds compared to the initial components.

In essence, the reaction between baking soda and lemon juice, leading to the formation of bubbles and the release of carbon dioxide gas, exemplifies a chemical change. This change involves the creation of new compounds with properties distinct from the original reactants, underscoring the typical attributes of a chemical reaction.