Acids and bases

Acids

Strong acids are $corrosive$

Some are weaker and are found in everyday things:

• $Citric acid$: lemons, oranges and other citrus fruits
• $Carbonic$ acid: rain water and fizzy drinks
• $Lactic acid$: sour milk and anaerobic respiration
• $Hydrochloric acid$: stomach

Acids turn $litmus paper$ ==red==

Acids are $chemical opposites$ to bases

Bases

Bases that dissolve in water are called $alkali$

Strong bases are also $corrosive$

Bases turn $litmus$ ^^blue^^

Bases are $chemical opposites$ to acids

The pH scale

The scale goes from $0-14$

Shows how $strong$ an acid or a base is

• Less than 7: $acid$
• More than 7: $base$
• 7: $neutral$

$Neutral$: neither an acid or base, no change in colour

• Closer to 0: $stronger$ acid
• Closer to 14: $stronger$ base

The pH can be found using $Universal Indicator$ Paper (UI)

UI paper $changes colour$ to show the pH

pH can also be measured by an $electronic sensor$ => pH meter