Lesson 4: Acids and Bases

New Information

Acids

An acid is a substance that releases hydrogen ions (H+). 

The strength of the acid depends on how many hydrogen ions it can release.

These are their properties:

• Corrosive

  • Meaning it can burn/eat away at substances

• Turns blue litmus paper red

• Can conduct electricity

• Can be neutralised by bases.

Bases

An base is a substance that releases hydroxide ions (OH-). 

The strength of the base depends on how many hydroxide ions it can release.

These are their properties:

• Caustic

  • Meaning it can burn/eat away at organic substances

• Turns red litmus paper blue

• Can conduct electricity

• Can be neutralised by acids.

pH

pH is a special measurement of how acidic or basic a substances is.

It is found by measuring the concentration of hydrogen ions in a solution.

It is a scale from 0-14.

• 0-7 is acidic 

• 7 is neutral (not a base or acid)

• 7-14 is basic