Limewater is used in many science experiments and is easy to make on your own.
What is Limewater?
Limewater comes in two varieties. The first is natural. It’s water that contains a higher-than-normal amount of calcium carbonate or calcium sulfate. The second variety is manmade: “milk of lime.” It’s a solution made from lime, acted upon (or slaked) by water. Lime itself is a solid, white compound of calcium and oxygen. It’s made from burning limestone (a “stone” made mostly of calcite), shells, and bones.
What’s It Good For?
Limewater is used most often to extract impurities from sugar made from (sugar) beets.
It’s also used to make soft water from hard water.
Limewater is also a neutralizing agent; it makes everything from corn flour to wastewater beneficial or safer.
It can also be used to bleach products, everything from stone to human hair.
Finally, limewater can be used to supplement coral reef production.
How to Make the Solution
1. Put 1 teaspoon of calcium hydroxide in a clean glass jar, up to 1 gallon in size. (Limewater is a saturated solution, which means there will be some extra chemical that doesn’t dissolve. A teaspoon will result in a fully saturated solution whether you use a gallon jar or a smaller one.)
2. Fill the jar with distilled or tap water.
3. Shake the jar vigorously for 1-2 minutes, then let it stand for 24 hours.
4. Being careful not to stir up the sediment, pour the clearer solution off the top of the jar through a clean coffee filter or filter paper.
5. Repeat the filtering step, if necessary, to obtain a clear limewater solution. Store in a clean jar or bottle.
When carbon dioxide is bubbled into limewater, calcium carbonate (CaCO3) is produced. It precipitates out as a white suspended solid, making the solution appear cloudy.
