19,879
edits
Changes
PH
,no edit summary
===Meaning===
[[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.
===About pH===
: '''pH''' is written with a lower case p and an upper case H and refers to the 'power of Hydrogen' as there are free [[Hydrogen]] [[ion]]s in an [[acid]].
: [[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]].
: '''pH''' 7.0 is [[Neutral (Chemistry)|neutral]].
==Key Stage 4Foundation==
===Meaning===
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.
===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]] or [[pure]] [[water]] 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=====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. ==Higher=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]] or [[pure]] [[water]] 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]].