Calcium carbonate is one of the most popular chemicals which is first encountered in school classrooms, where the use of chalk (form of CaCO3) is found. It is found in the earth’s crust. It is also found in many forms such as marble, limestone, etc. Although they are available in various forms they are chemically similar and only differ physically. They are also referred to as calcite.
What is Calcium Carbonate?
- It is a chemical compound with the formula CaCO3.
- It is a white insoluble powder-like substance which occurs naturally in minerals, chalk, marble, limestone, calcite, shells, pearl, etc.
- Medicinally, it is used as an antacid or as a calcium supplement. It is also used as fillers in cosmetics. It is added to swimming pools as a disinfectant agent and as pH corrector.
- It finds extensive usage in the manufacturing industry as a building material (marble), ingredient for quick lime and cement.
- On the large scale, it is prepared by passing carbon dioxide gas through calcium hydroxide (slaked lime). However, if carbon dioxide is passed in excess, it forms the soluble calcium hydrogen-carbonate.
Ca(OH)2 + CO2→ CaCO3 + H2O
- At 1200K, calcium carbonate decomposes to give carbon dioxide and calcium oxide.
CaCO3 → CaO + CO2
- On reacting with dilute acids, calcium carbonate gives carbon dioxide.
CaCO3 + H2SO4 → CaSO4 + H2O +CO2
7 Uses for Calcium Powder
1) Calcium Powder as a Dietary Supplement
Of course, you can use this homemade calcium powder as a daily supplement! I would start out with a small amount–about 1/2 teaspoon for an adult and make adjustments up to 1 teaspoon from there. The average adult needs between 1,000 and 1,500 mg of absorbable calcium daily.
The amount of calcium in 1/2 teaspoon of eggshell calcium provides roughly 90% of your daily calcium, give or take plus other minerals. If you are using more than a 1/2 tsp and up to 1 whole teaspoon of calcium powder, you may want to split the amounts between meals. Too much calcium powder may irritate your digestive system.
Personally, I say listen to your body. If you are under a great deal of stress, it may be likely that your body is not able to absorb the calcium you need from foods, so supplementing may be a good idea. At any rate, if you find yourself craving foods rich in calcium (dairy, kale, spinach, etc.) then your body is telling you something. You can see a doctor to have tests run to determine if you are deficient in calcium, if you need more specifics. Personally, I just take a little every day for prevention.
2) Use to Cut the Acidity of Your Coffee
Yep! That’s right! I’ve been experimenting with this one! I heard that if you sprinkle a bit of calcium powder into the grounds before brewing your coffee, the acidity and bitterness is effectively reduced creating a more delicious coffee that is easier on your stomach. Personally, I find the coffee tastes smoother too!
And guess what? Not only is your coffee less acidic and tastier—it is also healthier because of the extra calcium you’re getting!
3) Use it as a Natural Calcium Supplement for Your Pets
You can sprinkle a bit into your pets’ food too. They don’t need a lot! We actually feed our dogs each a whole egg from our chickens each day. They don’t have a problem consuming the shells. However, if that is a concern for you, the powdered eggshell is very gentle.
4) Sprinkle it Around Your Plants
You can use it to provide extra mineral supplementation for your house plants or in your garden! Not only does it help provide extra nutrition for your plants, it may also keep the pest problem down, especially slugs and snails.
Many people just toss their eggshells out into the garden, and this is not necessarily a bad thing—BUT if you take the time to create calcium powder, you’ll have a much greater impact on keeping pests away from your plants (the sharp edges of the powder will kill them) and the shells will disintegrate into the soil much more quickly.
5) Make a Face Mask!
This article has directions for a recipe for a skin tightening face mask. The eggshell powder in it provides nutrition for your skin as well as being slightly exfoliating. I try to put this on my face once a week. It’s a GREAT mask for mature skin, I can tell you!
Did you know that many movie stars over the decades have used eggs to help firm and tighten their skin? Yep! Before fancy, expensive plastic surgery and fillers were in vogue, more natural methods were used.
6) Make Your Own Sidewalk Chalk
Chalk is very high in calcium carbonate, and you can make your own with eggshell powder! You can find detailed directions PLUS a worksheet in case you are a homeschool mom or a teacher! I haven’t actually tried this (yet), but I have plans for this to be one of the projects I do with my grand daughter(s) this summer! Here is the article!
Calcium powder makes an excellent scrubbing medium. And if you combine it with some vinegar, you’ll find it cuts through just about anything!
Preparation of CaCO3
CaCO3 is obtained by using carbon dioxide and slaked lime as raw materials. When carbon dioxide is passed through slaked lime, calcite is obtained. Another method to obtain calcite is by adding sodium carbonate to calcium chloride.
Ca (OH)2 + CO2 → CaCO3 + H2O
CaCl2 + Na2CO3 → CaCO3 + 2NaCl
When carbon dioxide is passed in excess it leads to the formation of calcium hydrogen-carbonate.
Properties of CaCO3
- It is a fluffy powder.
- It has low solubility in water.
- It decomposes to give carbon dioxide when heated up to 1200K.
- When it reacts with a dilute acid, it liberates carbon dioxide as a by-product.
CaCO3+H2SO4 → CaSO4+H2O+CO2