Indicators and pH Scale

Which characteristics describe an acid?

• tastes sour, litmus indicator turns red

• tastes bitter, litmus indicator turns blue

• tastes sweet and sour, litmus indicator turns red

• tastes sour and bitter, litmus indicator turns blue

Which of the following is a alkaline?

• carbonated water

• lime juice

• vinegar

• dishwashing detergent

What property do all three of these fruits have in common?

• taste bitter sweet

• cannot conduct electricity

• have pH below 7

• turn litmus paper blue

What property do all three of these household items have in common?

• sometimes conduct electricity

• taste soapy

• have a pH equal to or above 7

• turn litmus paper blue

When Sally tested an unknown solution, her red litmus paper turned blue, but her blue litmus paper remained blue. What does this indicate?

• unknown is acidic

• unknown is alkaline

• unknown is neutral

• unknown can be acidic, alkaline or neutral

The pH scale is a range from

Which statement is true?

• the lower the pH, the stronger the acid

• the higher the pH, the stronger the acid

• the lower the pH, the more neutral the acid

• the higher the pH, the weaker the alkali

A very strong acid would have a pH of

• 1

• 7

• 9

• 14

A weak alkali would have a pH of

• 8

• 7

• 6

• 14

If you have a solution that is very acidic with a pH of 3.5, what can you do to raise the pH of the solution?

• add an acid

• add more water

• increase the temperature

• add an alkaline