Lime water 2.5L
Llime-29660-2.5L

Calcium hydroxide, Ca(OH)2 (also known as lime or hydrated lime), adds hydroxide ions to water, thereby increasing its pH and alkalinity.

Limewater is a clear, saturated aqueous solution of calcium hydroxide, Ca(OH)₂.

It has an alkaline pH of 11-12, a bitter taste, and is widely used in science classrooms to test for carbon dioxide.

Bubble CO2 through lime water  and it will turn the solution milky due to the formation of a calcium carbonate precipitate.