Acids

Acid is a substance which produces hydrogen ions, H+, when it is dissolved in water.
All acids contain hydrogen but not all compounds that contain hydrogen are acids. It is the hydrogen ions produced that are responsible for the properties of acids.

Properties:
- Sour taste

- Dissolve in water to form solutions which conduct electricity

- Turn blue litmus paper red

- React with reactive metals to form hydrogen and a salt.
General equation for this reaction:
metal + acid -> salt + hydrogen

- React with carbonates to form a salt, carbon dioxide and water
General equation for this reaction:
carbonate + acid -> salt + water + carbon dioxide

- React with metal oxides and hydroxides to form a salt and water only
General equation for reaction of acid with metal oxide:
metal oxide + acid -> salt + water
General equation for reaction of acid with metal hydroxide:
metal hydroxide + acid -> salt + water

Acids show the properties of acids when they are dissolved in water. Acids dissociate in water to produce hydrogen ions which show the acidic properties.

Uses:
Sulphuric acid:
- Detergents
- Fertilisers
- Car batteries
Ethanoic acid:
- Preserve food (vinegar)
- Adhesives (glue)
Hydrochloric acid:
- Leather processing
- Cleaning metals