Intro to Acids & Bases

Lemon juice has a pH of 2.3.

Which word best describes lemon juice based on the pH?

• acid

• base

• neutral

• salt

Tags

NGSS.MS-PS1-2

Priscila tested a sample of an unknown solution with litmus paper. The paper turned a dark blue and had a pH of 12. Which of the following chemicals is most likely in the solution?

• H2SO4

• H2O

• CaCl2

• KOH

Tags

NGSS.MS-PS1-2

Acidic solutions are those that contain an excess of:

• H2 molecules

• H2O molecules

• H+ ions

• OH- ions

Which pH value represents a solution with the lowest OH- ion concentration?

• 1

• 7

• 10

• 14

A 0.1 M solution of HCl contains:

• fewer H3O+ ions than OH- ions

• more H3O+ ions than OH- ions

• an equal number of H3O+ and OH-

• neither H3O+ nor OH- ions

The pH of milk is 6.4. Based on this information, which of the following statements best describes milk?

• It is very basic.

• It is very acidic.

• It is slightly basic.

• It is slightly acidic.

A sample of vinegar has a pH of 5, and a sample of rainwater has a pH of 6. Which of the following statements best describes these two substances?

• Both samples are bases, and vinegar is more basic.

• Both samples are acids, and vinegar is more acidic.

• Both samples are bases, and rainwater is more basic.

• Both samples are acids, and rainwater is more acidic.

Given the following solutions:

Solution A: pH of 10

Solution B: pH of 7

Solution C: pH of 5

Which list has the solutions placed in order of increasing H+ concentration?

• A, B, C

• B, A, C

• C, A, B

• C, B, A

Which of the following best describes a substance that is defined as an acid?

• Has a pH from 1-6 and has more H3O+ ions than OH- ions

• Has a pH from 8-14 and has more H3O+ ions than OH- ions

• Has a pH from 1-6 and has more OH- ions than H3O+ ions

• A neutral substance that has equal amounts of H3O+ and OH- ions

Phenolphthalein is an indicator that turns pink when added to a basic solution. In which solution would phenolphthalein turn pink?

• NaOH

• HCl

• H2O

• NaCl