Question

two acid base indicators

Answer 1

$\bf{Indicators}$ are substances which change their $\bf{colour}$ or $\bf{odour}$ when introduced to Acid or Base.

EXAMPLES ARE:-

$\bf{NATURAL}$ =>

• Turmeric
• Litmus (Solution/Paper)

$\bf{SYNTHETIC}$ =>

• Universal Indicator
• Phenolphthalein

$\bf{OLFACTORY \:\:INDICATORS}$ =>

• Vanilla
• Onion

Answer 2

Natural indicators

• Litmus
• Turmeric
• Red cabbage leaves

Synthetic indicators

• Methyl orange
• Phenolphthalein
• Methyl red

Olfactory indicators

• Vanilla essence
• Clove oil

Hope it helps !!