Effervescence when lime juice is dropped on baking soda

When lime juice is dropped on baking soda, a brisk effervescence takes place. This is because a gas is evolved during this reaction. The correct answer is option 'C', which states that the gas evolved is carbon dioxide.

Explanation:

When lime juice, which is acidic in nature, comes into contact with baking soda, which is a basic compound, a chemical reaction occurs. This reaction is known as an acid-base reaction or a neutralization reaction.

The reaction between the acid (lime juice) and the base (baking soda) can be represented by the following equation:

Lime juice (acid) + Baking soda (base) → Carbon dioxide (gas) + Water + Salt

The acid in lime juice is citric acid, and the base in baking soda is sodium bicarbonate. When these two compounds react, they produce carbon dioxide gas, water, and a salt. The salt formed in this reaction is sodium citrate.

Reason for effervescence:

The effervescence, or the brisk bubbling and fizzing, occurs due to the release of carbon dioxide gas. When the acid (citric acid) in lime juice reacts with the base (sodium bicarbonate) in baking soda, carbon dioxide gas is produced as one of the products.

The carbon dioxide gas is released in the form of bubbles, which gives rise to the effervescence. The reaction is exothermic, meaning it releases heat energy. This heat energy helps in the formation of carbon dioxide bubbles, making the effervescence more pronounced.

Other gases produced:

While carbon dioxide gas is the major gas evolved in this reaction, small amounts of other gases like hydrogen and oxygen may also be produced. However, their presence is not significant compared to carbon dioxide. Therefore, option 'C', which states that all three gases are produced, is the correct answer.