Indicators Acids and Bases

Bases will turn litmus paper __________, while acids will turn litmus paper __________.

• blue.....red
• red.....blue
• pink.........colourless
• colourless..........pink

The pH of a strong acid would be:

• 1-2
• 5-6
• 8-9
• 12-13

The pH of a strong base would be:

• 1-2
• 5-6
• 8-9
• 13-14

Indicators are substances that changes color when exposed to solutions with different pH values.

• True

• False

What is the color of litmus indicator in a solution with pH 3?

• blue

• red

What is the color of phenolphthalein in a solution with pH 12?

• colorless

• pink

What is the color of phenolphthalein in a solution with pH 6?

• colorless

• pink

What is the color of bromothymol blue in a solution with pH 5?

• yellow

• blue

What is the color of methyl orange in a solution with pH 5?

• yellow

• red

What is the color of methyl orange in a solution with pH 10?

• yellow

• red