Alka-Seltzer is a common antacid used to relieve an upset stomach. Alka-Seltzer and other fizzing tablets produce carbon dioxide-filled bubbles when placed in water. As the carbon dioxide is produced, ...

An curved arrow pointing right. Astronaut Terry Virts shows what it looks like when an effervescence, such as an Alka-Seltzer tablet, dissolves in water in outer space. This demonstration was ...