Changes

[[File:pHScale.png|right|300px|thumb|A '''pH''' scale with the colours of [[Universal Indicator]] at those '''pH''' values and some examples of [[substance]]s at those '''pH''' values.]]The '''pH''' scale is a numbered list from 1 0 to 14 that is used to identify how [[Acid|acidic]] or [[Base|basic]] a [[substance ]] is.

: [[Acid]]s range from 0-6.9 on the have a '''pH''' scale of less than 7 with the strongest [[acid]]s being at '''pH''' 0. : [[Base]]s range from 7.1-14 on the have a '''pH''' scale greater than 7 with the strongest [[base]]s being at '''pH''' 14. Remember [[alkali]]s are a [[base]] [[dissolve]]d in [[water]].

==Key Stage 4Foundation=====Meaning===The '''pH''' scale is a numbered list from 0 to 14 that is used to identify how [[Acid|acidic]] or [[Base|basic]] a [[substance]] is. ===About the pH Scale===: The '''pH''' of a [[solution]] is determined by the strength and [[concentration]] of [[Hydrogen Ion (Chemistry)|Hydrogen ions]] in an [[acid]] or [[Hydroxide Ion (Chemistry)|Hydroxide ions]] in an [[alkali]].: An [[acid]] will have a greater [[concentration]] of [[Hydrogen Ion (Chemistry)|Hydrogen ions]] the lower on the '''pH''' scale.: An [[alkali]] will have a greater [[concentration]] of [[Hydroxide Ion (Chemistry)|Hydroxide ions]] the higher on the '''pH''' scale.: A [[Neutral (Chemistry)|neutral]] [[solution]] will have an equal [[concentration]] of [[Hydrogen Ion (Chemistry)|Hydrogen ions]] and [[Hydroxide Ion (Chemistry)|Hydroxide ions]] and have a '''pH''' of 7. ==Key Stage 4 Higher==

The '''pH''' scale is a numbered list from 1 0 to 14 that is used to identify how [[Acid|acidic]] or [[Base|basic]] a [[substance ]] is.

====Foundation====: The '''pH''' of a [[solution]] is determined by the strength and [[concentration]] of [[Hydrogen Ion(Chemistry)|Hydrogen ions]] in an [[acid]] or [[Hydroxide Ion(Chemistry)|Hydroxide ions]] in an [[alkali]].: An [[acid]] will have a greater [[concentration]] of [[Hydrogen Ion (Chemistry)|Hydrogen ions]] the lower on the '''pH''' scale.: An [[alkali]] will have a greater [[concentration]] of [[Hydroxide Ion (Chemistry)|Hydroxide ions]] the higher on the '''pH''' scale.: A [[Neutral (Chemistry)|neutral]] [[solution]] will have an equal [[concentration]] of [[Hydrogen Ion (Chemistry)|Hydrogen ions]] and [[Hydroxide Ion (Chemistry)|Hydroxide ions]] and have a '''pH''' of 7.: In [[acid]]s for a '''pH''' decrease of 1 there must be 10 times greater [[concentration]] of [[Hydrogen Ion (Chemistry)|Hydrogen ions]] in [[solution]].  ===References=======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 ''pH scale, pages 107-8, GCSE Chemistry, Hodder, AQA '']:[https://www.amazon.co.uk/gp/product/1471851354/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851354&linkCode=as2&tag=nrjc-21&linkId=9012a0d354024419214fb3ad5ac44ba0 ''Ph scale, pages 209-10, GCSE Combined Science Trilogy 1, 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 ''pH scale, pages 96-99, GCSE Chemistry; Third Edition, Oxford University Press, 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 ''pH, pages 124, 125, 128, 129, 237, GCSE Combined Science Trilogy; Chemistry, CGP, 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=ad276ad49df77ab4b40ab4fd0fe10154 ''pH, pages 128, 234, GCSE Combined Science; The Revision Guide, CGP, 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 ''pH, pages 131, 148-9, 153, 167, 328-9, GCSE Chemistry; Student Book, Collins, 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 ''pH, pages 146, 147, 150, 153, 154, 315, GCSE Chemistry, CGP, AQA '']:[https://www.amazon.co.uk/gp/product/0198359373/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359373&linkCode=as2&tag=nrjc-21&linkId=952a73bbb09d222ecc4b50d200679849 ''pH, pages 45-48, GCSE Biology; Third Edition, Oxford University Press, 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=9e29fad914244909903e5e93f8a01d206 ''pH, pages 51-53, 108, GCSE Chemistry; The Revision Guide, CGP, AQA '']:[https://www.amazon.co.uk/gp/product/0008158754/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158754&linkCode=as2&tag=nrjc-21&linkId=27ad53b0283feeff7fc5ae04a9e205f418 ''pH, pages 97, 98-9, 101, 103, 348-9, GCSE Biology; 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 ''pH, pages 105, 106, 209, GCSE Combined Science; The Revision Guide, CGP, 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 ''pH, pages 118, 120-124, 323, GCSE Chemistry, CGP, 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 ''pH, pages 43, 44, GCSE Chemistry; The Revision Guide, CGP, 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 ''pH; pH probes, page 110, GCSE Chemistry; The Revision Guide, CGP, Edexcel '']

====HigherOCR====: In [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 ''pH, page 112, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR '']:[acidhttps://www.amazon.co.uk/gp/product/0198359829/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359829&linkCode=as2&tag=nrjc-21&linkId=90e8d7b4f039d53035238fa0320fe00b ''pH, pages 112-113, 118-119, Gateway GCSE Chemistry, Oxford, 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 ''pH, pages 43, 44, Gateway GCSE Chemistry; The Revision Guide, CGP, OCR '']s for a :[https://www.amazon.co.uk/gp/product/1782945660/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945660&linkCode=as2&tag=nrjc-21&linkId=83aa4500ad7759e7f401a1c5ba5df758 ''pH; and enzymes, page 18, Gateway GCSE Biology; The Revision Guide, CGP, OCR '']:[https://www.amazon.co.uk/gp/product/1782945660/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945660&linkCode=as2&tag=nrjc-21&linkId=83aa4500ad7759e7f401a1c5ba5df758 ''pH; and measuring, page 110, Gateway GCSE Biology; The Revision Guide, CGP, 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 ''pH; effect on enzymes, page 16, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR ' decrease of 1 there must be 10 times greater ']:[https://www.amazon.co.uk/gp/product/0198359810/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359810&linkCode=as2&tag=nrjc-21&linkId=d768d99f1a06f7c12fab40e5aef85a55 ''pH; enzyme-controlled reactions, page 35, Gateway GCSE Biology, Oxford, OCR '']:[concentrationhttps://www.amazon.co.uk/gp/product/0198359810/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359810&linkCode=as2&tag=nrjc-21&linkId=d768d99f1a06f7c12fab40e5aef85a55 ''pH; of soil, page 133, Gateway GCSE Biology, Oxford, 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 ''pH; pH meters, page 112, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR ''] of :[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 ''pH; pH meters, pages 43, 103, Gateway GCSE Chemistry; The Revision Guide, CGP, OCR '']:[Hydrogen Ion|Hydrogen ionshttps://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 ''pH; pH probes, pages 112, 220, 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 ''pH; pH probes, pages 43, 103, Gateway GCSE Chemistry; The Revision Guide, CGP, OCR ''] in :[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 ''pH; pH scale, page 112, Gateway GCSE Combined Science; The Revision Guide, CGP, OCR '']:[solution]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 ''pH; pH scale, pages 43, 44, Gateway GCSE Chemistry; The Revision Guide, CGP, OCR ''].