Calcium phosphate (Ca3(PO4)2) is a mineral found in teeth and bones. It helps to make them strong and healthy. It is also used as a dietary supplement to prevent calcium deficiency.
| IUPAC Name | Calcium phosphate |
| Molecular Formula | Ca3(PO4)2 |
| CAS Number | 7758-87-4 |
| Synonyms | Tricalcium phosphate, Bone phosphate, Calcium orthophosphate, Tribasic calcium phosphate, TCP |
| InChI | InChI=1S/3Ca.2H3O4P/c;;;21-5(2,3)4/h;;;2(H3,1,2,3,4)/q3*+2;;/p-6 |
Calcium Phosphate Properties
Calcium Phosphate Formula
The chemical formula for calcium phosphate is Ca3(PO4)2, which indicates that it contains three calcium ions and two phosphate ions. The formula is used to calculate the amount of calcium phosphate needed in chemical reactions. Calcium phosphate is an important component of teeth and bones and is also used in various industrial applications, such as food additives and fertilizers.
Calcium Phosphate Molar Mass
The molar mass of Ca3(PO4)2 is 310.18 g/mol. It is calculated by adding the atomic mass of calcium, phosphorus, and oxygen, which are 40.08 g/mol, 30.97 g/mol, and 15.99 g/mol, respectively. The molar mass is an important parameter in determining the amount of Ca3(PO4)2 required in a chemical reaction.
Calcium Phosphate Boiling Point
Ca3(PO4)2 does not have a defined boiling point, as it decomposes before reaching its boiling point. When heated, Ca3(PO4)2 decomposes into calcium oxide and phosphorus pentoxide, releasing water vapor. The decomposition temperature depends on the type of Ca3(PO4)2 and the heating rate.
Calcium Phosphate Melting Point
The melting point of Ca3(PO4)2 depends on the type of Ca3(PO4)2. The melting point of tricalcium phosphate, the most abundant form of Ca3(PO4)2 in nature, is approximately 1670 °C. Dicalcium phosphate has a melting point of around 1400 °C, while monocalcium phosphate melts at approximately 109 °C.
Calcium Phosphate Density g/mL
The density of Ca3(PO4)2 varies depending on the type of Ca3(PO4)2. Tricalcium phosphate has a density of approximately 3.14 g/mL, while dicalcium phosphate has a density of around 2.31 g/mL. Monocalcium phosphate has a density of approximately 2.22 g/mL.
Calcium Phosphate Molecular Weight
The molecular weight of Ca3(PO4)2 is 310.18 g/mol, which is the sum of the atomic weights of calcium, phosphorus, and oxygen. The molecular weight is important in calculating the amount of Ca3(PO4)2 needed in chemical reactions.
Calcium Phosphate Structure
Ca3(PO4)2 has a complex crystal structure that depends on the type of Ca3(PO4)2. Tricalcium phosphate has a hexagonal crystal structure, while dicalcium phosphate has a monoclinic crystal structure. Monocalcium phosphate has a tetragonal crystal structure. Ca3(PO4)2 crystals are composed of calcium ions and phosphate ions arranged in a specific pattern.
| Appearance | White powder or crystals |
| Specific Gravity | 3.14 |
| Color | White |
| Odor | Odorless |
| Molar Mass | 310.18 g/mol |
| Density | 3.14 g/mL (tricalcium phosphate) |
| Melting Point | 1670 °C (tricalcium phosphate) |
| Boiling Point | Decomposes before boiling |
| Flash Point | N/A |
| Water Solubility | 0.002 g/100 mL (at 25 °C) |
| Solubility | Soluble in acids, insoluble in water |
| Vapour Pressure | N/A |
| Vapour Density | N/A |
| pKa | pKa1: 1.9, pKa2: 6.7, pKa3: 12.0 |
| pH | 5.5-7.5 (10% suspension in water) |
Calcium Phosphate Safety and Hazards
Ca3(PO4)2 is generally considered safe for human consumption and has no significant health hazards. It is a natural mineral found in bones and teeth and is used as a dietary supplement in many forms. Ca3(PO4)2 is also used in the food industry as a food additive and as a dough conditioner. However, excessive consumption of Ca3(PO4)2 supplements can lead to adverse effects, such as stomach upset, constipation, and even kidney damage. Additionally, exposure to high levels of Ca3(PO4)2 dust in the workplace can cause respiratory problems. Therefore, it is important to use Ca3(PO4)2 supplements and products in moderation and to follow safety guidelines in industrial settings.
| Hazard Symbols | None known |
| Safety Description | 26-36/37/39: Wear suitable protective clothing, gloves and eye/face protection. |
| UN IDs | N/A |
| HS Code | 28352500 |
| Hazard Class | Not classified |
| Packing Group | Not applicable |
| Toxicity | Low toxicity |
Calcium Phosphate Synthesis Methods
There are several methods for synthesizing Ca3(PO4)2, including precipitation, hydrothermal synthesis, sol-gel process, and solid-state reaction.
The precipitation method involves combining calcium and phosphate ions in an aqueous solution, which results in the formation of a precipitate through a chemical reaction. The experimenter then washes and dries the precipitate to obtain the desired Ca3(PO4)2 compound.
Hydrothermal synthesis involves the reaction of calcium and phosphate sources in a high-pressure, high-temperature environment. To obtain the desired Ca3(PO4)2 compound, one wash and dries the resulting product.
In the sol-gel process, one converts a sol, or colloidal suspension, into a gel and then dries it to obtain the desired Ca3(PO4)2 compound. This method allows for precise control over the composition and morphology of the resulting compound.
The solid-state reaction involves the mixing of calcium pyrophosphate and calcium carbonate in a solid state and then heating the mixture to promote a chemical reaction. To obtain the desired Ca3(PO4)2 compound, one should wash and dry the resulting product.
Calcium Phosphate Uses
Ca3(PO4)2 has a variety of uses in different industries due to its unique properties. Some of the common uses of Ca3(PO4)2 are:
- Dietary supplements: Commonly used in dietary supplements as a source of calcium and phosphorus, which are essential minerals for bone health.
- Food and beverage industry: Used as a food additive in many processed foods, including baked goods, dairy products, and beverages. In baking, people use it as a leavening agent and a source of calcium.
- Pharmaceutical industry: Used in the pharmaceutical industry as a filler and binder in tablets and capsules. Certain drugs can have their bioavailability improved by using it as a coating agent.
- Agriculture: Used as a fertilizer to provide plants with essential nutrients like calcium and phosphorus.
- Dentistry: Used in dentistry to remineralize teeth and to restore tooth enamel.
- Biomedical engineering: Also used in biomedical engineering to develop bone graft substitutes and to improve the properties of biomaterials used in bone tissue engineering.
Questions:
Q: Why does the addition of acid increase the solubility of calcium phosphate?
A: The addition of acid increases the solubility of Ca3(PO4)2 by protonating the phosphate ions, which makes them more soluble in water. The protonated phosphate ions form acidic Ca3(PO4)2, which is more soluble than the neutral form.
Q: How many grams of phosphorus are in 500.0 grams of calcium phosphate?
A: The molar mass of Ca3(PO4)2 is 310.18 g/mol. The compound has a 2:3 ratio of phosphorus to calcium, so the molar mass of phosphorus is 30.97 g/mol. Therefore, there are 81.62 grams of phosphorus in 500.0 grams of Ca3(PO4)2.
Q: Is calcium phosphate soluble?
A: Ca3(PO4)2 has low solubility in water, with a solubility product of 1.8 x 10^-29. However, its solubility can be increased by the addition of acids.
Q: What is the percentage of oxygen, by mass, in calcium phosphate?
A: The molar mass of Ca3(PO4)2 is 310.18 g/mol. The atomic mass of oxygen is 16.00 g/mol, and there are 8 oxygen atoms in one mole of Ca3(PO4)2. Therefore, the mass of oxygen in one mole of Ca3(PO4)2 is 8 x 16.00 = 128.00 g. The mass of Ca3(PO4)2 is 310.18 g, so the percentage of oxygen, by mass, is (128.00 g / 310.18 g) x 100% = 41.23%.
Q: Is Ca3(PO4)2 soluble in water?
A: Ca3(PO4)2 is not very soluble in water, with a solubility product of 1.3 x 10^-33.
Q: What is the molar mass of Ca3(PO4)2?
A: The molar mass of Ca3(PO4)2 is 310.18 g/mol.
Q: What is Ca3(PO4)2?
A: Ca3(PO4)2 is a chemical compound that consists of three Ca2+ and two PO43- ions. It is a white, odorless powder that is insoluble in water.
Q: What is the gram formula mass of Ca3(PO4)2?
A: The gram formula mass of Ca3(PO4)2 is 310.18 g/mol.