PH Indicators

Which aqueous solution would turn blue litmus red?

• HCl

• NaOH

• K₂CO₃

• NaCl

The small intestine has a pH value of 7.3. What color would it turn when tested with the indicator thymol blue?

• red

• yellow

• blue

• green

Which indicator would turn yellow in a solution with a pH of 9.8?

• methyl orange

• bromthymol blue

• bromcresol green

• thymol blue

Which pH is the most acidic?

• 6.7

• 2.0

• 8.0

• 7.3

What is an indicator in Chemistry?

• Chemical dyes that can change colour according to pH

• A small light bulb on a car

• A chemical involved in a chemical reaction

• A substance used to neutralise an acid

How can you measure the pH of a substance?

• Use a pH probe

• Use universal indicator

• Use litmus paper

• Use phenolphthalein

What is a substance that is one color in an acid and another color in a base? 

• Oxidizer

• Indicator

An indicator will ______________ when it is in contact with an acid or base

• Bubble

• Form a new substance

• Change color

• Stay the same color

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

• blue.....red

• red.....blue

• pink.........colourless

• colourless..........pink

According to the image, the substance tested is a...

• Acid

• Neutral

• Strong Acid

• Base