document.write( "Question 126703: a molecule of propane has 26 atoms. if there are 6 fewer hygrogen atoms than 3 times the number of carbon atoms, how many atoms does it contain \n" ); document.write( "
Algebra.Com's Answer #92839 by kev82(151)\"\" \"About 
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Chemistry answer:
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\n" ); document.write( "\n" ); document.write( "Propane has 3 carbon atoms (meth=1, eth=2, prop=3, but=4, pent=5, hex=6, hep=7, oct=8, ...) and it is an alkane (ends with -ane). The number of hydrogen atoms in an alkane is twice the number of carbons plus two. 2*3+2=6+2=8. So 3 carbons and 8 hydrogen.
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\n" ); document.write( "\n" ); document.write( "(This is definitely correct, so your question is wrong, the chemical is not propane)
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\n" ); document.write( "\n" ); document.write( "Maths answer:
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\n" ); document.write( "\n" ); document.write( "The chemical is made up of 26 atoms, and they are either carbon or hydrogen. So c+h=26. The number is hydrogen atoms is six less than three times the carbon, so h=3c-6. Substituting this into the first equation gives c+(3c-6) = 32, which rearranges to 4c=32, and then c=8. Using the second equation h=3c-6, h=3*8-6=24-6=18. So c=8, h=18.
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\n" ); document.write( "\n" ); document.write( "(This is in-fact an alkane, because h=2*c+2, and it is called octane.)
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\n" ); document.write( "\n" ); document.write( "English answer:\r
\n" ); document.write( "\n" ); document.write( "\"a molecule of propane has 26 atoms.\"
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\n" ); document.write( "\n" ); document.write( "\"how many atoms does it contain\"
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\n" ); document.write( "\n" ); document.write( "26! (although, like I said it definitely is not propane.
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