Question about alkane and alkene?
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Alkenes are more reactive than alkanes because they have a carbon-carbon double bond which is more susceptible to various reactions. Alkenes produce a sootier flame because the double bond is more difficult to combust.  Alkenes spotted on filter paper absorb iodine vapor and leave a brown spot. There is also a bromine test. Not available at Wal-Mart!
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To understand this question, you need to know what kind of product will be produced during a combustion. Generally, for a complete combustion of a hydrocarbon (contains only H and C), the product will be H2O and CO2. Depending on the C and H content in the hydrocarbon, you will produce different amount of H2O and CO2. \n\nOn the other hand, if it is an incomplete combustion (with limited supply of O2), apart from CO2 and H2O, you may also produce C and CO. The relative amount between them varies depending on the amount of O2 that is made available. With very limited amount of O2, more C (soot) will be produced. This leads to the "sooty" flame you are seeing.\n\nIn order to explain why generally alkenes require less O2 to burn compared to alkanes, let's compare ethane (2 C alkane) and ethene (2 C alkene). \n\nEthane has a formula C2H6 while ethene has a formula C2H4. Their corresponding balanced equation for combustion are:\n\nC2H6 + 7/2 O2 → 2 CO2 + 3 H2O\nC2H4 + 3 O2 → 2CO2 + 2 H2O\n\nAs you see, since both compounds have same number of C, they both produce 2 mole of CO2 for every mole of compound. However, since they have different number of H, the number of moles of H2O produced will be different. Since H2O has a fixed formula, in order to produce it, you need to supply O2. That's why the two compounds require different amount of O2.\n\nThe reason that you see a sooty flame is due to the fact that you don't have enough oxygen supply during the burning process. You can easily confirm this by using just a Bunsen burner (but be very carefully!!!). First, turn on your Bunsen burner with the air hole closed. The flame you see at the moment should be a luminous flame. It is golden yellow color. Now, if you carefully put a glass plate (hold with clamp or other device) on top of the flame and slowly move towards the tip of the burner (but don't cover it completely), you should see the plate will get "darker" by the flame. This is the soot produced during the combustion. Now, take away the plate, open the air hole in the burner to the max. You should see a the flame turns to blue. If you put the glass plate (with the soot marks) back to the flame, you can see the flame can slowly "clean up" the plate (if enough O2 is supplied with the flame) and the soot will disappear. The soot is turn back to CO2 due to the excess of O2.
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propane\nbutane\nhydrogen\nmethane\nacetylene\nmethyl chloride\nnickel carbonyl\nhydrogen sulfide\n\n\nhundred of others
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Pentane is a Highly Flammable Liquid which may form Explosive Mixtures with air.  It chemically combines with the oxygen in the atmosphere to give carbon dioxide and water:\n\nC5H12 (l) + 8O2 (g) --> 5CO2 (g) + 6H2O (g)
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Isopropane.\n\n"The number of hydrogen atoms associated with a given skeleton of carbon atoms may vary.  When the chain or ring carries the full complement of hydrogen atoms, the hydrocarbon is said to be "saturated".  Such hydrocarbons are known as paraffins, paraffinic hydrocarbons, or alkanes/cycloalkanes. The "paraffin" term was common in the oil industry, because of the waxy characteristics of crude which contains these molecules.  The term "alkanes" is common among chemists.\n\nStraight-chain  structures are "normal paraffins", branch-chain structures are "isoparaffins", and ring-type structures are "cycloparaffins" or naphthenes.  Thus for three hydrocarbons with five carbon atoms (i.e. all "pentanes") we have several structures."
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Try drawing them out.  Octane has a total of 18 isomers - 7 of them have hexane as the longest carbon chain. First try placing an ethyl on one of the carbons in the hexane chain and see how many possible constitutional arrangements are possible.(Only one possible - on carbon 3)  Then work with 2 methyl groups - try placing them on the hexane chain and see how many different combinations are possible.\n\nHere they are:\n\n3-Ethylhexane\n2,2-Dimethylhexane\n2,3-Dimethylhexane\n2,4-Dimethylhexane\n2,5-Dimethylhexane\n3,3-Dimethylhexane\n3,4-Dimethylhexane
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According to Zaitzev rule your answer is correct. I don't know if they expected you to say that still you'll get some 3-methyl-1-pentene as a by-product, or if they also wanted you to note that the E (trans) stereoisomer of 3-methyl-2-pentene is the main product.\n\nBy the way, the way you wrote the question people mistake the alkoxy base (RO-) with "dash or"
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Alkanes-such as methane (CH4) can pass through the lipid bilayer.
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=======\n\ngem is right.\n\nYou will get a mixture of two isomers of bromopropane.
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r u really serious !!! how can one find a pie bond in an alkane????
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Br2 reacts with the double bond of an alkene.    The double bond disappears and the carbon atoms of the former double bond are now bonded to a Br atom.  Since Br2 is broken apart, then it no longer has the color.
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Water and carbon dioxide are the only products when the hydrocarbon fuel (i.e. fuel composed *entirely* of both Carbon and Hydrogen atoms) burns in a *complete* reaction.\n\nHydrogen is a fuel that is not a hydrocarbon.  If you burn hydrogen in a complete reaction you will only get water.\n\nCarbon is also not a hydrocarbon.  You will only get carbon dioxide.\n\nAlso, in reality, a reaction almost never goes to completion, i.e. all the reactants are not converted to products.  You can have some of the original reactant left over, and you can also have intermediate products (like carbon monoxide and nitrogen oxides)
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The general formula for alkanes is CnH2n+2
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C2H2 - acetylene\nC2H6 - ethane\nCH4 - methane\nC8H18 - octane\nC2H3OH - ethanol\nthis list is a mile long
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it is a mixture of hydrocarbons containing few carbons. octane is one constituent
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All hydrocarbons.  They start with gaseous methane (CH4) dissolved in the oily liquid, then through heavier dissolved gases with 2 to 5 carbon atoms per molecule, then liquids with every posible number of carbon atoms per molecule from 6 (benzene) to 8 (octane) to scores and scores, then waxes (the stuff of Vaseline) which have up to hundreds.  Sometimes there are sulphur-based impurities.\n\nRefining the oil is the process of separating the different weights of components.  Car and aeroplane fuel is roughly from C6 to C10, diesel fuel is heavier, and heating oils and lubricating oils are heaviest.
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2-methylheptane\n3-methylheptane \n4-methylheptane \n\n2,2-dimethylhexane \n2,3-dimethylhexane \n2,4-dimethylhexane \n2,5-dimethylhexane \n3,3-dimethylhexane \n3,4-dimethylhexane \n3-ethylhexane \n\n2,2,3-trimethylpentane \n2,2,4-trimethylpentane \n2,3,3-trimethylpentane \n2,3,4-trimethylpentane \n3-ethyl-2-methylpentane \n3-ehtyl-3-methylpentane\n\n2,2,3,3-tetramethylbutan\noops n octane