Acids and bases

Examine the results (color change) of the pH paper shown in the picture. What type of substance was tested?

• an acid

• a base

• a neutral substance

• none of the above

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

• Bubble
• Form a new substance
• Change color
• Stay the same color

If the substance is neutral, what would the pH be?11

• 3

• 5

• 7

• 9

• 11

Ocean water is only slightly basic. What might its pH value be?

• 5

• 8

• 12

• 2

The strongest bases have pH values close to

• 0

• 14

• 7

• 5

Which of the following pH values represents a base?

• 2.1

• 4.6

• 6.8

• 8.1

Which of the following is a property of a base?

• bitter taste

• reacts with metals

• salty

• sour taste

Milk is a very weak acid. What might its pH value be?

• 6.5

• 7.8

• 4.2

• 12.2

Which of these pH values represent an acid?

• 4

• 8

• 10

• 12

A substance is found to have the following characteristics:

Very bitter taste

Feels slippery to the touch

Produces OH- ions when dissolved in water

In what category would the substance be classified?

• acid

• base

• enzyme

• fatty acid