Acids and Bases

Holly has an unknown substance in a beaker. She wants to determine the relative pH of the unknown substance. She places a piece of blue litmus paper into the substance, and the litmus paper stays blue.
The substance in the beaker

• is a base.
• has a neutral pH.
  
• is an acid.
• does not have a pH.

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.

The pH of a solution is tested, and it is found to be a basic solution. Of the following choices, what could the pH have been?

• 3
• 9
• 7
• 5

Values from 0-14 that determine the acidity of a solution

• Punnett Square
• Matrix
• pH scale
• Math number line 

Which of the following is a basic solution?

• household ammonia
• HCl dissolved in water
• Vinegar
• Pure water

When found in food, bases often taste _______.

• Sour

• Bitter

• Salty

• Soggy

Four solutions are tested and found to have the following pH values. Which of these substances would be considered the weakest acid?

• Lemon Juice - pH=2

• Apple Juice - pH=4.5

• Shower Cleaner - pH=5.5

• Hydrogen Peroxide - pH=7

When dissolved in water, bases produce:

• acids
• salts
• hydrogen ions
• hydroxide ions

Which of the following is true about acids and bases?

• 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 base

Which type of ion does a base produce when it is dissolved in water?

• oxide
• oxygen
• hydrogen
• hydroxide