Acids and Bases

Pure water has a pH of 7. Pure water _______.

• is a base
• is a neutral substance
• could be either an acid or a base
• is an acid

Many cleaning solutions are bases. Which of the following is a property of most bases?

• feels slippery
• white color
• can only be liquid
• tastes sour

Human blood has a pH between 7.35 and 7.45. Which of the following best describes human blood?

• strongly acidic
• slightly acidic
• strongly basic
• slightly basic

Carrie's teacher hands out test tubes filled with different chemicals and tells the students to identify their liquid as an acid, base, or neutral chemical. Carrie's test tube contains a clear chemical. She adds phenolpthalein to her test tube and gently moves the tube from side to side. A few moments later, the chemical in the test tube turns bright pink.
What type of chemical does Carrie have?

• Carrie has a neutral chemical.
• Carrie has an acidic chemical.
• Carrie has a basic chemical.
• The type of chemical Carrie has cannot be determined.

Which of the following statements is correct?

• Blue litmus paper turns red when placed in a base.
• Red litmus paper turns blue when placed in a base.
• Blue litmus paper stays blue when placed in an acid.
• Red litmus paper stays red when placed in a base.

Which is the stronger acid?

• pH 1
• pH 4
• pH 8
• pH 13

In a base phenolphthalein will give what color?

• Green
• Blue
• Pink
• Clear

Turns litmus blue.

• Acids
• Bases
• Salts
• All

Turns litmus red

• Acids
• Bases
• All

Which has a pH above 7?

• Acid
• Base