CH4 (methane) is not significantly soluble in water. 1 Methane is a nonpolar molecule, while water is a polar solvent. 2 3 The difference in polarity between methane and water prevents them from forming strong attractions, resulting in low solubility.
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Key Takeaways: Is CH4 Soluble in Water?
- Methane (CH4) is insoluble in water because water is a polar solvent and methane is a nonpolar molecule.
- Methane can dissolve in other nonpolar solvents, such as hexane, toluene, and carbon tetrachloride.
- Water and nonpolar solvents are immiscible, meaning they do not mix well together.
Why is methane (CH4) insoluble in water?
Methane (CH4) is considered insoluble in water due to the significant difference in polarity between the two substances. The solubility of a substance in water depends on its ability to interact with water molecules through intermolecular forces. 4
Water is a highly polar molecule, meaning it has a partial positive charge on its hydrogen atoms and a partial negative charge on its oxygen atom. This polarity allows water molecules to form strong hydrogen bonds with each other and with other polar substances. 5
However, methane is a nonpolar molecule, consisting of four hydrogen atoms bonded to a carbon atom, and it lacks any significant charge separation. 1
Since water and methane have different polarities, they do not form strong intermolecular interactions with each other. Water molecules tend to cluster around each other through hydrogen bonding, which makes it difficult for nonpolar molecules like methane to integrate into this network. 6
Instead, methane molecules tend to aggregate with other nonpolar molecules and exclude water molecules, leading to low solubility in water.
It’s important to note that while methane is not highly soluble in water, it can still dissolve to some extent due to weak dispersion forces between nonpolar molecules. 7
However, compared to polar substances that readily dissolve and form solutions in water, methane’s solubility is considered very low.
Can methane dissolve in other solvents?
Yes, methane (CH4) can dissolve in other nonpolar solvents. 8 Nonpolar solvents have similar polarity characteristics to methane, allowing them to interact favorably and form solutions. Nonpolar solvents lack significant positive or negative charges and do not engage in strong hydrogen bonding or dipole-dipole interactions.
Examples of nonpolar solvents in which methane can dissolve include:
- Hexane (C6H14): Hexane is a common nonpolar solvent and is frequently used in laboratories. It has a low polarity and can dissolve nonpolar substances like methane effectively. 9
- Toluene (C7H8): Toluene is another nonpolar solvent commonly used in organic chemistry. It is effective in dissolving nonpolar compounds, including methane.
- Carbon tetrachloride (CCl4): Carbon tetrachloride is a nonpolar solvent that was commonly used in the past but is less prevalent due to its environmental impact. It can dissolve nonpolar substances like methane.
These solvents have weak intermolecular forces similar to methane, allowing for favorable interactions and dissolution. However, it’s important to note that these solvents are not miscible with water, meaning they do not mix well with water, as water is a highly polar solvent.
Further reading
Why is Sugar (Sucrose) Soluble in Water?
Is BaSO4 (Barium Sulfate) Soluble in Water?
Is CaCO3 (Calcium Carbonate) Soluble in Water?
Why is Calcium Soluble in Water?
Why is KNO3 (Potassium Nitrate) Soluble in Water?
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References
- P. (n.d.). Methane. Methane | CH4 | CID 297 – PubChem. https://pubchem.ncbi.nlm.nih.gov/compound/297
- Uni-hamburg.de https://www1.biologie.uni-hamburg.de/b-online/library/newton/Chy251_253/Lectures/Polarity/Polarity.html
- 2.11: Water – Water’s Polarity. (2018, July 5). Biology LibreTexts. https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Book%3A_General_Biology_(Boundless)/02%3A_The_Chemical_Foundation_of_Life/2.11%3A_Water_-_Waters_Polarity
- Chapter 9.2: Solubility and Structure – Chemistry LibreTexts. (2016, January 3). Chapter 9.2: Solubility and Structure – Chemistry LibreTexts. https://chem.libretexts.org/Courses/Prince_Georges_Community_College/CHEM_2000%3A_Chemistry_for_Engineers_(Sinex)/Unit_3%3A_States_of_Matter/Chapter_9%3A_Solutions/Chapter_9.2%3A_Solubility_and_Structure
- Hydrogen bonds in water (article) | Khan Academy. (n.d.). Khan Academy. https://www.khanacademy.org/science/ap-biology/chemistry-of-life/structure-of-water-and-hydrogen-bonding/a/hydrogen-bonding-in-water
- Usgs.gov https://www.usgs.gov/media/images/strong-polar-bond-between-water-molecules-creates-water-cohesion
- Pruteanu, C. G., Ackland, G. J., Poon, W. C. K., & Loveday, J. S. (2017, August 4). When immiscible becomes miscible—Methane in water at high pressures. Science Advances, 3(8). https://doi.org/10.1126/sciadv.1700240
- Actachemscand.org http://actachemscand.org/pdf/acta_vol_14_p1124-1128.pdf
- Srivastan, S., Darwish, N. A., Gasem, K. A. M., & Robinson, R. L. (1992, October). Solubility of methane in hexane, decane, and dodecane at temperatures from 311 to 423 K and pressures to 10.4 MPa. Journal of Chemical & Engineering Data, 37(4), 516–520. https://doi.org/10.1021/je00008a033