ACIDS

What are acids?

Acids are substances that taste sour and can be strong or mild.

Examples in everyday life:

• Lemon juice

• Tomato

• Apple

• Vinegar

• Tamarind

Properties of acids:

• Sour taste

• Can be corrosive if strong

• Turn blue litmus paper → red

ALKALIS (Bases that dissolve in water)

What are alkalis?

Alkalis are substances that taste bitter and feely soap slippery.

Examples in everyday life:

• Soap

• Baking soda

• Detergent

• Bleach

• Milk of magnesia (medicine)

Properties of alkalis:

• Bitter taste

• Slippery to touch

• Turn red litmus paper → blue

Litmus Paper

We use litmus paper to test if something is acid or alkali.

• Blue → Red = Acid

• Red → Blue = Alkali

Fun Fact

Bee sting contains acid, while wasp sting contains alkali — that’s why they hurt differently!