Difference between revisions of "Cracking"

Latest revision as of 01:07, 4 December 2019

Key Stage 4

Meaning

Cracking is a Thermal Decomposition process in which large hydrocarbon molecules are broken into smaller hydrocarbon molecules.

About Cracking

Cracking is often done because Crude Oil contains more large hydrocarbon molecules than can be used and not enough short hydrocarbon molecules than are needed.

When Crude Oil fractions are cracked the long alkanes are broken down into smaller alkanes and alkenes.

Cracking is done at very high temperatures (500°C) and uses either a catalyst to aid the reaction or steam.

When an alkane is cracked into smaller pieces there are not enough Hydrogen [[atom]s to produce two saturated hydrocarbons. One of the hydrocarbons must be unsaturated and therefor will have a double bond.

Examples


If butane were cracked.		An alkane and an alkene are produced.

Cracking a hydrocarbon can produce many possible products:

Hexadecane → Decane + Hexene

Hexadecane → Decane + Butene + Ethene

Decane → Pentane + Pentene

Decane → Hexane + Butene

References

@@ Line 13: / Line 13: @@
 |-
 |[[File:StructuralDiagramButane.png|center|200px]]
-|[[File:ArrowRight.png|center|200px]]
+|[[File:ArrowRight.png|center|100px]]
 |[[File:StructuralDiagramEthane.png|center|200px]]
-|[[File:AdditionSign.png|center|200px]]
+|[[File:Addition.png|center|100px]]
-|[[File:StructuralDiagramEthene.png|center|200px]]
+|[[File:StructuralDiagramEthene.png|center|100px]]
 |-
-| style="height:20px; width:200px; text-align:center;" |Ethandioate and Ethandiol can [[Chemical Reaction|react]] together in a '''Condensation Polymerisation'''.
+| style="height:20px; width:200px; text-align:center;" |If [[butane]] were '''cracked'''.
 |
-|colspan="3"| style="height:20px; width:200px; text-align:center;" |An [[alkane]] and an [[alkene]] are [[Product|produced]].
+|colspan="3"|An [[alkane]] and an [[alkene]] are [[Product|produced]].
 |}
+[[Cracking]] a [[hydrocarbon]] can [[product|produce]] many possible [[product]]s:
+Hexadecane → Decane + Hexene
+: <chem>C16H34 -> C10H22 + C6H12</chem>
+Hexadecane → Decane + Butene + Ethene
+: <chem>C16H34 -> C10H22 + C4H8 + C2H4</chem>
+Decane → Pentane + Pentene
+: <chem>C10H34 -> C5H12 + C5H10</chem>
+Decane → Hexane + Butene
+: <chem>C10H34 -> C6H14 + C4H8</chem>
+===References===
+====AQA====
+:[https://www.amazon.co.uk/gp/product/1782945598/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945598&linkCode=as2&tag=nrjc-21&linkId=ad276ad49df77ab4b40ab4fd0fe09814 ''Cracking (of hydrocarbons), page 149, GCSE Combined Science; The Revision Guide, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/1782945962/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945962&linkCode=as2&tag=nrjc-21&linkId=476bb5c8d1dfb5c08ac81b6d4d1c98d8 ''Cracking (of hydrocarbons), page 226, 227, GCSE Chemistry, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/1782945571/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945571&linkCode=as2&tag=nrjc-21&linkId=9e29fad914244909903e5e93f8a01d96 ''Cracking (of hydrocarbons), page 77, GCSE Chemistry; The Revision Guide, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/178294639X/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=178294639X&linkCode=as2&tag=nrjc-21&linkId=51599bb45a2bfaf7c1b6a978b2ca2616 ''Cracking (of hydrocarbons), pages 194, 195, GCSE Combined Science Trilogy; Chemistry, CGP, AQA '']
+:[https://www.amazon.co.uk/gp/product/1471851362/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851362&linkCode=as2&tag=nrjc-21&linkId=7d78d70a2044ee9982dae010c94af92a ''Cracking, pages 147-8, GCSE Combined Science Trilogy 2, Hodder, AQA '']
+:[https://www.amazon.co.uk/gp/product/0198359381/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359381&linkCode=as2&tag=nrjc-21&linkId=47c8d1ae58d8b3a5e2094cd447154558 ''Cracking, pages 154-55, GCSE Chemistry; Third Edition, Oxford University Press, AQA '']
+:[https://www.amazon.co.uk/gp/product/1471851346/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851346&linkCode=as2&tag=nrjc-21&linkId=3ac654f4b0da781c49c855a1af4c92ea ''Cracking, pages 176-7, GCSE Chemistry, Hodder, AQA '']
+:[https://www.amazon.co.uk/gp/product/0008158762/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158762&linkCode=as2&tag=nrjc-21&linkId=a0fffa35b3ea49a63404f6704e0df7cc ''Cracking, steam, page 236, GCSE Chemistry; Student Book, Collins, AQA '']
+:[https://www.amazon.co.uk/gp/product/0008158762/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158762&linkCode=as2&tag=nrjc-21&linkId=a0fffa35b3ea49a63404f6704e0df7cc ''Cracking; catalytic, page 236-7, GCSE Chemistry; Student Book, Collins, AQA '']
+====Edexcel====
+:[https://www.amazon.co.uk/gp/product/1782945741/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945741&linkCode=as2&tag=nrjc-21&linkId=30da4f2178da182547b62a7329d13b57 ''Cracking, page 140, GCSE Combined Science; The Revision Guide, CGP, Edexcel '']
+:[https://www.amazon.co.uk/gp/product/1292120193/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120193&linkCode=as2&tag=nrjc-21&linkId=572df39392fb4200db8391d98ae6314e ''Cracking, page 274, GCSE Combined Science, Pearson Edexcel '']
+:[https://www.amazon.co.uk/gp/product/1782945725/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945725&linkCode=as2&tag=nrjc-21&linkId=694be7494de75af3349537d34e13f7f0 ''Cracking, page 90, GCSE Chemistry; The Revision Guide, CGP, Edexcel '']
+:[https://www.amazon.co.uk/gp/product/1292120215/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120215&linkCode=as2&tag=nrjc-21&linkId=8f96ddb76196848bafdb124354e4cf77 ''Cracking, pages 160, 190, GCSE Chemistry, Pearson, Edexcel '']
+:[https://www.amazon.co.uk/gp/product/1782948147/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948147&linkCode=as2&tag=nrjc-21&linkId=f63dcd8345f4e49c717b39a228a36c7c ''Cracking, pages 262, 263, GCSE Chemistry, CGP, Edexcel  '']
+====OCR====
+:[https://www.amazon.co.uk/gp/product/1782945695/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945695&linkCode=as2&tag=nrjc-21&linkId=ceafcc80bcad6b6754ee97a0c7ceea53 ''Cracking, page 143, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR  '']
+:[https://www.amazon.co.uk/gp/product/1782945679/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945679&linkCode=as2&tag=nrjc-21&linkId=a2db42f7b4bdf10cafaafa3bb9120940 ''Cracking, page 94, Gateway GCSE Chemistry; The Revision Guide, CGP, OCR '']