Check Point Acid and Bases

A group of students conducts an experiment to identify which of their unknown liquids are acids and which are bases. They use a pH indicator and collect the following data:

Which statement identifies the acids and bases in the data table?

• Liquid 3 has a pH higher than pure water, so it is an acid. Pure water has a neutral pH, so it is a base.

• Liquid 2 has a pH lower than pure water, so it is a base. Pure water has a neutral pH, so it is an acid.

• Liquid 3 has a pH higher than pure water, so it is a base. Liquid 2 has a pH lower than pure water, so it is an acid.]

• Pure water has a neutral pH, so it is a base. Liquid 1 has a pH lower than pure water, so it is an acid.

Tags

NGSS.MS-PS1-2

1. Kiva notices that the ingredients label on her drink includes citric acid. She wonders how the acid affects her drink.

Which statement describes a possible effect citric acid could have on the drink?

•  It could add a sour flavor to the drink.

• It could add a bitter flavor to the drink.

• It could make the drink more neutral.

• It could make the drink turn red litmus paper blue.

How can she use the droppers to lower the pH?

• Add drops of the concentrated base to the beaker.

• Add drops of the concentrated acid to the beaker.]

• Add drops of pure water to the beaker.

• Add a few drops from each dropper to the beaker.

Tags

NGSS.MS-PS1-2

What test can the students perform to correctly and safely identify acids and bases? They used litmus paper. The blue litmus turned red which indicates.......?

• Base

• Neutral

• alkaline

• acid

Tags

NGSS.MS-PS1-2

A student uses litmus to test an unknown substance. The red litmus turns blue which indicates. the solution is .......?

• Base

• Neutral

• Acid

• positive hydrogen

Tags

NGSS.MS-PS1-2

The pH scale is used to measure how acidic or basic something is. A pH value lower than 7 indicates a substance is _______, while a pH value higher than 7 is considered ________. Pure water is considered _______, with a pH of_______ .

Choose the option that identifies the missing terms, in order of appearance in the sentences.

• acidic; acidic; neutral; 12

•  acidic; basic; neutral; 7

• basic; acidic; basic; 1

• 1. neutral; basic; basic; 7