Question

Kelly gave the following instructions to her science class:

• Place an empty water bottle on the table and remove the lid. Carefully pour 10 ml of vinegar into the bottle.
• Open up the mouth of the balloon and have your lab partner put 1 teaspoon of baking soda into the balloon.
• Without spilling any of the baking soda, stretch the mouth of the balloon over the mouth of the bottie.
Turn the balloon completely upright so that the baking soda inside the balloon pours into the betlewith the vinegar. Watch!
The baking soda looked like it dissolved in the vinegar. Keshon and Taraji watched as the balloon expanded and filled with gas. Was this a physical or chemical

Answer 1

The expansion of the balloon due to gas as observed by Keshon and Taraji is a chemical change.

The experiment involves a chemical change. The combination of vinegar (acetic acid) and baking soda (sodium bicarbonate) initiates a chemical reaction, forming carbon dioxide gas, water, and salt. This reaction is represented as:

`\( \text{NaHCO}_3 + \text{CH}_3\text{COOH} \rightarrow \text{CO}_2 + \text{H}_2\text{O} + \text{CH}_3\text{COONa} \)`

The observed expansion of the balloon indicates the production of gas in the form of carbon dioxide. Unlike a physical change, where substances retain their identity, a chemical change involves the creation of new substances with distinct properties, as demonstrated in this experiment.