pH Scale Quiz

On the pH scale, an acid is a compound that produces a solution with a pH __________ 7.

On the pH scale, a base is a compound that produces a solution with a pH __________ 7.

What pH does a neutral substance have?

• 5

• 6

• 7

• 8

Which of the following is the weakest acid?

• bananas (pH 5)

• tomatoes (pH 4)

• cheese (pH 6)

• orange juice (pH 3)

Tomatoes have a pH of about 4. How many times more acidic are tomatoes versus pure water?

Eggs have a pH of about 8. How many times more basic are eggs versus orange juice (pH 3)? 

Why does pure, clean rainwater have a pH of 5.6?

What is the cause of acid rain?

Our teeth enamel is made of a basic material called hydroxyapatite. Knowing this, would you predict the pH of human saliva to be acidic? Why?

Approximately what pH value does human saliva actually have?