Difference between revisions of "Acid"
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| style="height:20px; width:200px; text-align:center;" |Milk has a small amount of [[Lactic Acid]] giving it [[pH]] 6.5. | | style="height:20px; width:200px; text-align:center;" |Milk has a small amount of [[Lactic Acid]] giving it [[pH]] 6.5. | ||
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| + | ==Key Stage 4== | ||
| + | ===Meaning=== | ||
| + | An [[acid]] is a [[compound]] which is able to donate [[Hydrogen Ion|H<sup>+</sup> ions]] when [[dissolve]]d in [[water]] to produce a [[solution]] with a [[pH]] less than [[Neutral (Chemistry)|7]]. | ||
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| + | ===About Acids=== | ||
| + | ====Foundation==== | ||
| + | : [[Acid]]s form from [[Ionic Compound|ionic compounds]] where there is an [[Ionic Bond|ionic bond]] between a [[Hydrogen]] [[ion]] and another part of the [[molecule]]. | ||
| + | : When an [[acid]]ic [[compound]] [[dissolve]]s in [[water]] the [[Hydrogen Ion|Hydrogen ion]] becomes dissociated from the [[molecule]] and is free to move separately in the [[solution]]. | ||
| + | : The [[Hydrogen Ion|Hyrdrogen ion]]s in an [[acid]] will accept [[electron]]s from any [[metal]] which is higher on the [[Reactivity Series|reactivity series]] than [[Hydrogen]]. This is because those [[metal]]s can lose their [[electron]]s more easily than the [[Hydrogen]] [[atom]]. | ||
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| + | ====Higher==== | ||
| + | : | ||
Revision as of 10:23, 4 January 2019
Contents
Key Stage 3
Meaning
An acid is a chemical dissolved in water that has a pH less than 7.
About Acids
- Acids can be an Irritant, Harmful or Corrosive and should be handled with care.
- When an acid is dissolved in solution the Hydrogen atoms in the molecule become free to move around and these are what make it an acid.
- Acids can be concentrated or dilute.
- Acids can be weak or strong which depends on the type of acid and the concentration.
- Acids turn Litmus paper red.
- Acids turn Universal Indicator pink, red, orange or yellow depending on the strength of the acid.
Some common Acids you should know:
- Hydrochloric Acid - Found in the stomach.
- Citric Acid - Found in Citrus fruits.
- Ethanoic Acid - The common name for vinegar.
- Sulphuric Acid - Found in Electrical Cells.
Examples
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| Car batteries contain Sulphuric Acid at around pH 0. | Citrus fruits have Citric Acid in them at around pH 2. | Vinegar is made of Ethanoic Acid at around pH 2.5. |
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| Fizzy drinks contain Carbonic Acid at around pH 3. | Coffee is slightly acidic at pH 5. | Milk has a small amount of Lactic Acid giving it pH 6.5. |
Key Stage 4
Meaning
An acid is a compound which is able to donate H+ ions when dissolved in water to produce a solution with a pH less than 7.
About Acids
Foundation
- Acids form from ionic compounds where there is an ionic bond between a Hydrogen ion and another part of the molecule.
- When an acidic compound dissolves in water the Hydrogen ion becomes dissociated from the molecule and is free to move separately in the solution.
- The Hyrdrogen ions in an acid will accept electrons from any metal which is higher on the reactivity series than Hydrogen. This is because those metals can lose their electrons more easily than the Hydrogen atom.