Molecular Weight of Water (H2O)
Identification of Water Chemical Compound
| Chemical Formula | H2O |
|---|---|
| Molecular Weight | 18.01528 g/mol |
| IUPAC Name | water |
| SMILES String | O |
| InChI | InChI=1S/H2O/h1H2 |
| InChIKey | XLYOFNOQVPJJNP-UHFFFAOYSA-N |
Molecular Weight Description
The water molecule consists of 2 Hydrogen atom(s) and 1 Oxygen atom(s) - a total of 3 atom(s). The molecular weight of water is determined by the sum of the atomic weights of each constituent element multiplied by the number of atoms, which is calculated to be:
$$ 18.01528 · \frac{g}{mol} $$
The exact term of the above molecular weight is “molar mass”, which is based on the atomic mass of each element. Molecular weight is actually an older term of “relative molar mass” or “molecular mass”, which is a dimensionless quantity equal to the molar mass divided by the molar mass constant defined by 1 g/mol.
Molecular masses are calculated from the standard atomic weights of each nuclide, while molar masses are calculated from the atomic mass of each element. The atomic mass takes into account the isotopic distribution of the element in a given sample.
chemical table area
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- Name: ethanol
- CAS #: 64-17-5
- Formula: C2H5OH
- Smiles: CCO
- InChI: InChI=1S/C2H6O/c1-2-3/h3H,2H2,1H3
- InChIKey: LFQSCWFLJHTTHZ-UHFFFAOYSA-N
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Additional Information for Identifying Water Molecule
-
Structure Data File (SDF/MOL File) of water
The structure data file (SDF/MOL File) of water is available for download in the SDF page of water, which provides the information on atoms, bonds, connectivity and coordinates of water. The water structure data file can be imported to most of the chemistry-related software, providing three-dimensional visualization and further analysis.
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Chemical structure of water
The molecular structure image of water is available in chemical structure page of water, which provides the molecular geometry information, i.e., the spatial arrangement of atoms in water and the chemical bonds that hold the atoms together.
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Chemical formula of water
The molecular formula of water is given in chemical formula page of water, which identifies each constituent element by its chemical symbol and indicates the proportionate number of atoms of each element.
-
InChI (IUPAC International Chemical Identifier) information of water
In addition to the molecular weight information, the structural information of water in a textual expression is available via InChi. The full standard InChI of water is given below:
InChI=1S/H2O/h1H2
It can provide a way to encode the molecular information of water to facilitate the search for the compound information in databases and on the web.
The condensed, 27 character standard InChIKey (hashed version of the full standard InChI) of water is:
InChIKey=XLYOFNOQVPJJNP-UHFFFAOYSA-N
It may allow easier web searches for water. The InChIKey, however, needs to be linked to the full InChI as well in order to get back to the original structure of the water as the full standard InChI cannot be reconstructed from the InChIKey.
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Other names (synonyms) or registry numbers of water
There may be different names of the water compound depending on the various situations of industrial applications, which are given below including the registry numbers if available:
- AR-1L8208
- OXO
- HYD
- eau
- DIS
- 8O
- 558440-22-5
- Water, for embryo transfer, sterile-filtered, BioXtra, suitable for mouse embryo
- Water solution, contains 10.0 % (v/v) methanol, 0.10 % (v/v) trifluoroacetic acid
- Water solution, contains 0.10 % (v/v) formic acid, 50.0 % (v/v) acetonitrile
- Water solution, contains 0.1 % (v/v) formic acid, 20 % (v/v) acetonitrile
- Water solution, contains 0.05 % (w/v) ammonium formate, 0.1 % (v/v) formic acid
- Sterile Diluent for Merck Sharp & Dohme Corp. Live Attenuated Virus Vaccines
- Water, for cell biology, free of endotoxins, ultrafiltered and autoclaved
- Water solution, contains 0.1 % (v/v) trifluoroacetic acid, for HPLC
- Water solution, HPLC grade, contains 0.035 % (v/v) acetic acid
- Physicianscare Ophthalmic Solution Eyewash Purified Water, 98.3%
- Water, sterile-filtered, BioReagent, suitable for cell culture
- Water, for molecular biology, DEPC-treated and sterile filtered
- Water solution, for HPLC, contains 0.1 % (v/v) formic acid
- Water solution, contains 0.06 % (v/v) trifluoroacetic acid
- Water solution, contains 0.05 % (v/v) trifluoroacetic acid
- Water solution, contains 10 mM ammonium acetate, for HPLC
- Water solution, contains 0.1 % (v/v) ammonium hydroxide
- Density Standard 998 kg/m3, H&D Fitzgerald Ltd. Quality
- Bacteriostatic Water for Injection USP-pre-filled Syringe
- Water, for HPCE, for luminescence, for UV-spectroscopy
- I14-102543
- Water, deuterium-depleted, <=1 ppm (Deuterium oxide)
- Water solution, contains 0.10 % (v/v) acetic acid
- Water solution, contains 0.05 % (v/v) acetic acid
- Water solution, 0.005N in sulfuric acid, for HPLC
- Diluting Medium for Insulin Zinc Injectable Suspension
- First Aid Direct Buffered Eyewash Sterile Isotonic
- Water, deuterium-depleted, 99.99995 atom %
- D00001
- Water, packaged for use in deposition systems
- Water, deuterium depleted, deuterium 2-3 ppm
- Diluting Medium for Soluble Insulin Injection
- Diluting Medium for Isophane Insulin Injection
- Water, ACS reagent, for ultratrace analysis
- Sterile purified water in containers (JP17)
- Fad First Aid Direct Buffered Eye and Skin
- Emergency Eye Wash, Pw, Sterile Ster-aide
- Water, ultrapure, Spectrophotometric Grade
- Water for injection in containers (JP17)
- Plum Duo Emergency Eyewash Ph Neutralizing
- A-med Brand First Aid Eye and Skin-rinse
- Sterilized Water for Injections Ph. Eur.
- Sterile Isotonic Buffered Genuine Eyewash
- Physicianscare Ophthalmic Solution Eyewash
- Airlife Sterile Water for Inhalation USP
- Xpect Buffered Eyewash Sterile Isotonic
- Sterile Water for Injection 100% USP
- 558440-53-2
- Xpect First Aid Buffered Eye and Skin
- RTR-011310
- Bacteriostatic Water for Injection USP
- Water with 0.1% trifluoroacetic acid
- Sterile Water for Injection, U.S.P.
- Sterile Water for Inhalation USP 3ml
- Plum Emergency Eyewash Ph Neutralizing
- E-Toxate(TM) Water, endotoxin, free
- Sterile Water for Inhalation U.S.P.
- Purified water in containers (JP17)
- Collyrium for Fresh Eyes - Eye Wash
- Water, tested according to Ph.Eur.
- Medi-first Plus First Aid Eye Wash
- Walgreens Sterile Soothing Eye Wash
- Water, deionized water, ACS 1L
- Sperian Eyesaline Emergency Eyewash
- [OH2]
- Sterile Water for Injection, USP
- Salinaax Eye Wash and Skin Flush
- Xpect First Aid Buffered Eyewash
- Sterile Water for Irrigation USP
- Sterile Water for Inhalation USP
- Water, Molecular Biology Reagent
- Water for Injection Sterile USP
- Sterile Water for Injection USP
- Hydrogen hydroxide (HH or HOH)
- HMDB02111
- Green Guard First Aid Eye Wash
- Aerowash Eyewash and Skin-rinse
- Water, BioPerformance Certified
- Medi-first First Aid Eye Wash
- Bacteriostatic water for injection in plastic container
- 059QF0KO0R
- Water, ultrapure, HPLC Grade
- WATER, For PCR Applications
- Water, for ion chromatography
- Water for injection (JP17)
- Fad First Aid Direct Eyewash
- C C(KO
- Water, demineralized, p.A.
- GLUCOSE 4-O4 GROUP
- Cederroth Emergency Eye Wash
- DEUTERIUM OXIDE- D
- Water, HPLC gradient grade
- Thesafetydirector Aquapreserv
- Sterile water for injection in plastic container
- Dihydrogen monoxide (DHMO)
- Water, RNase, DNase-free
- Distilled water, for HPLC
- Plum Duo Emergency Eyewash
- Water, for TOC analysis
- Water (JP17/USP)
- Sperian Eyesaline Eyewash
- Purified water (JP17)
- Eyewash Flushing Solution
- Water, purified (USP)
- DISORDERED SOLVENT
- an unknown oxygen source
- Water, sterile filtered
- Water for Injection BP
- Physicianscare Eye Wash
- Industrial Neutral-eyes
- Plum Emergency Eyewash
- OXO GROUP
- Water, Endotoxin-free
- Water, DEPC-Treated
- BOUND OXYGEN
- HYDROXY GROUP
- Family Care Eye Wash
- Haws Eyewash Additive
- Water, LC/MS
- Sterile water (TN)
- Water, PCR Reagent
- UNKNOWN
- Rugby Eye Irrigating
- Water, HPLC Plus
- Water, HPLC grade
- Water, ACS reagent
- First Aid Eye Wash
- Eyesaline Concentrate
- Water, HPLC
- Bacteriostatic Water
- Pure Water Density Standard, UKAS ISO/IEC17025 and ISO Guide 34 certified, density: 0.9982 g/mL at 20 C, density: 0.9970 g/mL at 25 C
- Water for injection, bacteriostatic
- Scienceware Eyewash
- Medi-first Eyewash
- Sterile Water Inj
- Salinaax Eye Wash
- Sterile water in plastic container
- Eys Eye Wash
- Buffered Eye-lert
- Boraqua Eye Wash
- Major Eye Wash
- Hydrohydroxic acid
- hydrogen hydroxide
- Eye Wash
- DI water
- Bouton Eye Wash
- Eye Clean
- Hydrogen monoxide
- water-
- Eye Stream
- Dorama-neo
- Water Additive
- Sterile Diluent
- Hydric acid
- Eye Irrigating
- Aqua Purificata
- Hydroxic acid
- Hydroxy radical
- Water for irrigation, sterile
- Water for inhalation, sterile
- Wasser
- Ocufresh
- Eyewash
- Tritiotope
- Water for injection, sterile
- dihydridooxygen
- acqua
- Sterile water for inhalation
- Water, sterile purified
- Water, purified sterile
- Water for hemodialysis
- Sterile purified water
- UNK
- GTE
- Pur-wash
- aqua
- agua
- Water, distilled, conductivity or of similar purity
- HOH
- DEUTERIUM OXIDE- D
- MFCD00011332
- Water, for HPLC
- Hydrol
- Ice
- Bacteriostatic water for injection
- BOUND WATER
- H2O
- Water (distilled)
- Sterile water for irrigation
- Sterile water for injection
- Water for injection
- Water, distilled
- Water, sterile
- oxidane
- Deionized water
- DHMO
- steam
- Dihydrogen Monoxide
- Water, mineral
- Sterile water
- Water, deionized
- Water, purified
- Water vapor
- 7732-18-5
- Purified water
- Distilled water
- Dihydrogen oxide
Water Identification Summary Frequently Asked Questions (FAQs)
| What’s the formula of water? |
|---|
| H2O |
| How many atoms and what are the elements in the water molecule? |
| 3 atom(s) - 2 Hydrogen atom(s) and 1 Oxygen atom(s) |
| How many chemical bonds and what types of bonds are in the water structure? |
| 2 bond(s) - 1 water molecule(s) |
| What’s the molar mass of water? |
| 18.01528 g/mol |
| What’s the SMILES format of water? |
| O |
| What’s the InChI format of water? |
| InChI=1S/H2O/h1H2 |
| What’s the InChIKey string of water? |
| XLYOFNOQVPJJNP-UHFFFAOYSA-N |
3183
The contents of this page can freely be shared if cited as follows:
Source: Chemical Compounds Deep Data Source (CCDDS; https://www.molinstincts.com) based on 41 patented QSQN and QN
technology
commercialized into Mol-Instincts database and ChemRTP, ChemEssen, Inc (2024).