A soda siphon uses a small, high-pressure carbon dioxide cartridge to carbonate water.
The volume of the high-pressure gas cartridge is 12 cm3.
The initial pressure of the gas inside the cartridge is 8000 kPa.
When the seal of the cartridge is broken, the gas expands into the space (headspace) above the water.
The gas expands to a total volume of 320 cm3.
Calculate the new pressure of the gas, assuming the temperature remains constant during this initial expansion.
As the gas expands into the headspace above the water, its temperature decreases. Using ideas about molecules, explain how this temperature decrease affects the pressure of the gas.
Some of the carbon dioxide gas molecules dissolve into the water. Suggest how this affects the pressure of the gas in the headspace and explain your answer.
When the valve is opened, the pressure of the gas forces the carbonated water out through a nozzle. The pressure outside the bottle is less than the pressure inside. Suggest what happens to the dissolved gas as the water leaves the bottle.
