Calcium carbonate vs Sodium bicarbonate: what is the difference?
Calcium carbonate is chalk, neutralising acid slowly and leaving calcium behind, while sodium bicarbonate is baking soda, neutralising it fast with a fizz.
Sources and notes
- The sentence under the titlefrom sourceMoleculeFinder comparison notesThe pair's answer line.
- The two drawingscomputedMoleculeFinder rule (RDKit MCS)Drawn the same way round on the skeleton they share. Aligned; 0 atoms differ, none to mark.
- Structural similaritycomputedRDKit Morgan/Tanimoto0.50 of 1, a Morgan fingerprint Tanimoto coefficient. It measures shape, not effect.
Side by side
| Calcium carbonate | Sodium bicarbonate | |
|---|---|---|
| Molecular weightCalculated PubChem | 100.09 g/molCCaO3 | 84.01 g/molCHNaO3 |
| Hydrogen-bond donorsCalculated PubChem | 0 | 1 |
| Where each turns upEditorial MoleculeFinder food and product lists |
|
|
| FamilyEditorial MoleculeFinder curated | Other | Other |
| Everyday groupEditorial MoleculeFinder curated | Nutrient | Food & flavor |
| Oral LD50Measured HSDB via PubChem | 6,450 mg/kgpure calcium carbonate, rat, oral | 4,220 mg/kgpure sodium bicarbonate, rat, oral |
| A single acute animal measure. It ranks nothing about human safety. | ||
Sources and notes
- Molecular weightcomputedPubChemComputed from the structure; the formula is under each weight.
- Hydrogen-bond donorscomputedPubChemThe hydrogens on nitrogen or oxygen that each molecule can lend to a hydrogen bond, counted from its structure.
- Where each turns upfrom sourceMoleculeFinder food and product listsEach amount is an editorial figure from our lists, not a measurement of any one product. Each mark is set by hand on the list, never inferred.
- Familyfrom sourceMoleculeFinder curated
- Everyday groupfrom sourceMoleculeFinder curated
- Oral LD50from sourceHSDB via PubChem
- Identifiersfrom sourcePubChemPubChem CID 10112 (Calcium carbonate) and 516892 (Sodium bicarbonate).
In more detail
Both are mild alkalis that neutralise stomach acid, and both appear on antacid labels, but they are different kinds of substance. Calcium carbonate, CaCO3 at 100.09, is chalk, limestone and eggshell: insoluble in water, it reacts only as acid reaches it, so it works slowly and leaves calcium behind, which is why it doubles as a calcium supplement. Sodium bicarbonate, NaHCO3 at 84.007, is baking soda: it dissolves readily, neutralises acid at once and releases carbon dioxide as it does, the fizz of an effervescent tablet and the lift in a cake. That reaction also means baking soda carries sodium, which calcium carbonate does not. Neither carries a GHS hazard label, and their reported oral LD50 values in rats are close, 6450 mg/kg for calcium carbonate and 4220 mg/kg for sodium bicarbonate.
Sources and notes
- The paragraphfrom sourceMoleculeFinder comparison notes
Questions
- What is the difference between Calcium carbonate and Sodium bicarbonate?
- Calcium carbonate is chalk, neutralising acid slowly and leaving calcium behind, while sodium bicarbonate is baking soda, neutralising it fast with a fizz.
- Is Calcium carbonate bigger than Sodium bicarbonate?
- Calcium carbonate is the heavier molecule, 100.09 g/mol against 84.01 g/mol for Sodium bicarbonate. Calcium carbonate is CCaO3 and Sodium bicarbonate is CHNaO3.
- Which has the lower reported LD50, Calcium carbonate or Sodium bicarbonate?
- Sodium bicarbonate, at 4,220 mg/kg (oral, rat), against 6,450 mg/kg (oral, rat) for Calcium carbonate. An LD50 is one acute animal measurement, and the two here were not necessarily measured in the same species, so it is a data point rather than a ranking of how dangerous either is to a person.
Sources and notes
- The answersfrom sourceMoleculeFinderThe first is the pair's answer line; the others are read off the table above.