Ime zasićeni ugljovodonici potiče od činjenice da alkani ne podležu nikakvoj adicionoj reakciji. Alkani su dosta hemijski nereaktivni, podležu reakciji samo u ekstremnim slučajevima (visoka temperatura i pritisak). Generalno se izdvajaju tri tipa reakcije kojima podležu alkani: C 29H 60 који служи као заштита од губитка влаге, док већина других биљака као заштиту користи биљне воскове који су по саставу естри. Numeriraju se atomi C, vodeći računa o smjeru brojanja: atomi C koji na sebe imaju vezan neki drugi atom ili skupinu atoma trebaju dobiti što manji mogući broj. Pri tome se atomi vodika ne računaju.

Fizičke osobine alkana zavise od nekoliko faktora. Prvi i najvažniji je broj ugljenikovih atoma. Drugi je struktura niza. Z naraščajočim številom ogljikovih atomov se dviguje tudi temperatura vnetišča, zato se alkani z velikim številom ogljikovih atomov zelo težko vnamejo. Če je količina kisika premajhna, nastajata ogljikov monoksid in/ali saje (ogljik): 2CH 4 + 3O 2 → 2CO + 4H 2O CH 4 + O 2 → C + 2H 2O

Koji je najjednostavniji alkan?

C-C везу: 1,54 А° а за C-H везу: 1,1 А°. Атомске орбитале су распоређење у замишљеном тетраедру тако да угао између C-H веза износи 109°28'. Сигма веза је релативно еластична и дозвољава ротирање око ње, а настаје чеоним коаксијалним преклапањем хибридних орбитала. Halogeniranje alkanov je zelo pomembenno za industrijsko pridobivanje halogeniranih ogljikovodikov. Reakcija poteka v treh stopnjah: a b c d e f g Thornton Morrison, Robert; Neilson Boyd, Robert. 1973. Organska kemija (Organic chemistry, third edition). New York University (prijevod Dragutin Kolbah). Allyn and Bacon Inc., Boston, Massachusetts. Zagreb. str.580 Initiation the halogen radicals form by homolysis. Usually, energy in the form of heat or light is required. Poskusi so pokazali, da pri halogeniranju nastane zmes vseh možnih izomerov, to pa ne pomeni, da je zmes produktov enaka statistični zmesi. Zaradi večje stabilnosti sekundarnih in terciarnih prostih radikalov se halogeni raje vežejo na sekundarne in terciarne ogljikove atome. Značilen primer je monobromiranje propana.

Alkani su zasićeni ugljikovodici koji imaju samo jednostruke kovalentne veze u molekulu. Njihov predstavnik je plin metan.Dragan and his colleague were the first to report about isomerization in alkanes. [28] Isomerization and reformation are processes in which straight-chain alkanes are heated in the presence of a platinum catalyst. In isomerization, the alkanes become branched-chain isomers. In other words, it does not lose any carbons or hydrogens, keeping the same molecular weight. [28] In reformation, the alkanes become cycloalkanes or aromatic hydrocarbons, giving off hydrogen as a by-product. Both of these processes raise the octane number of the substance. Butane is the most common alkane that is put under the process of isomerization, as it makes many branched alkanes with high octane numbers. [28] Other reactions [ edit ] In plants, the solid long-chain alkanes are found in the plant cuticle and epicuticular wax of many species, but are only rarely major constituents. [37] They protect the plant against water loss, prevent the leaching of important minerals by the rain, and protect against bacteria, fungi, and harmful insects. The carbon chains in plant alkanes are usually odd-numbered, between 27 and 33 carbon atoms in length, [37] and are made by the plants by decarboxylation of even-numbered fatty acids. The exact composition of the layer of wax is not only species-dependent but also changes with the season and such environmental factors as lighting conditions, temperature or humidity. [37] Kim, HyunJung; Kim, NamSun; Lee, DongSun (2000). "Determination of floral fragrances of Rosa hybrida using solid-phase trapping-solvent extraction and gas chromatography–mass spectrometry". Journal of Chromatography A. 902 (2): 389–404. doi: 10.1016/S0021-9673(00)00863-3. PMID 11192171. a b William Reusch. "Nomenclature – Alkanes". Virtual Textbook of Organic Chemistry. Archived from the original on 21 May 2016 . Retrieved 5 April 2007.

H 3 C C l + 2 N a + C l C H 2 C H 3 ⟶ { C H 3 C H 2 C H 3 C H 3 C H 3 C H 3 C H 2 C H 2 C H 3 + 2 N a C l {\displaystyle \mathrm {H_{3}CCl+2\ Na+ClCH_{2}CH_{3}\longrightarrow {\begin{cases}CH_{3}CH_{2}CH_{3}\\CH_{3}CH_{3}\\CH_{3}CH_{2}CH_{2}CH_{3}\end{cases}}+2NaCl} } Разпространение [ редактиране | редактиране на кода ] Strukturna izomerija je pojava dva ili više spoja imaju jednaku molekulsku formulu i molekulsku masu, ali se razlikuju po rasporedu atoma (a time i svojstvima). Pentan, primjerice, ima tri strukturna izomera:This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. ( January 2021) ( Learn how and when to remove this template message) Janssen, P. H.; Kirs, M. (2008). "Structure of the Archaeal Community of the Rumen". Appl Environ Microbiol. 74 (12): 3619–3625. Bibcode: 2008ApEnM..74.3619J. doi: 10.1128/AEM.02812-07. PMC 2446570. PMID 18424540. Kesselmeier, J.; Staudt, N. (1999). "Biogenic Volatile Organic Compounds (VOC): An Overview on Emission, Physiology and Ecology" (PDF). Journal of Atmospheric Chemistry. 33 (1): 22–38. Bibcode: 1999JAtC...33...23K. doi: 10.1023/A:1006127516791. S2CID 94021819. Archived from the original (PDF) on 13 March 2013.

Iniciacija: vezi, na primer Cl-Cl, se razcepijo (homoliza), tako nastanejo radikali Cl•. Za iniciacijo je potrebna toplotna ali svetlobna energija. Gornji kationi nisu striktno organski jer ne sadrže ugljik (osim metanija). Međutim, mnogi organski kationi dobivaju se substitucijom nekog elementa ili funkcijske skupine na vodikovo mjesto. The terms "base" and "alkali" are often used interchangeably, particularly outside the context of chemistry and chemical engineering. Vrelište im raste s porastom relativne molekularne mase, a pada s većim stupnjem razgranatosti lanca.

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Metabolism of Alkanes and Fatty Acids – eQuilibrator 0.2 beta documentation". equilibrator.weizmann.ac.il . Retrieved 11 April 2018. Since alkanes have high ionization energies, the mass spectra show weak ion currents. The fragmentation pattern can be difficult to interpret, but in the case of branched chain alkanes, the carbon chain is preferentially cleaved at tertiary or quaternary carbons due to the relative stability of the resulting free radicals. The fragment resulting from the loss of a single methyl group ( M−15) is often absent, and other fragments are often spaced by intervals of fourteen mass units, corresponding to sequential loss of CH 2 groups.