Question

The bubbles in a carbonated soft drink are produced when carbonic acid decomposes to form carbon dioxide and water. In a closed system, this equilibrium exists as

Why does a carbonated soft drink lose carbonation when the container is left open?


A.Water evaporates, which favors the formation of H2CO3.

B.Pressure decreases, which favors the formation of H2CO3.

C.The open container warms up, which causes more gas to escape.

D.CO2is removed, which favors the formation of H2CO3.

Answer 1

The bubbles in a carbonated soft drink show up when carbonic acid (H2CO3) decomposes to form carbon dioxide (CO2) and water (H2O). In a closed system, this equilibrium exists as:

H2CO3 ⇌ CO2+ H2O

B is the correct answer.

Carbonated drinks are sealed under high pressure so when a container is left open, pressure decreases which favors the formation of carbonic acid (H2CO3). It is weak acid which decomposes releasing CO2 in the form of bubbles.