2/28(W): Chemistry Checkpoint #13

Vinegar is a commercial form of acetic acid, HC₂H₃O₂(aq). One sample of vinegar has a pH value of 2.4.

State the color of bromthymol blue indicator in a sample of the commercial vinegar.

• Yellow

• Blue

• Red

• Pink

Match the following with the correct card

• pH 7.7 and Bromthymol blue

• Red

• pH 3.7 and Bromocresol green

• Pink

• pH 2.5 and Methyl orange

• Blue

• pH 10.0 and Phenolphthalein

• Yellow

Match the following with the correct card

• pH 9.8 and Thymol blue

• Yellow

• pH 10.0 and Methyl orange

• Pink

• pH 10.5 and Bromocresol green

• Blue

• pH 12.0 and Phenolphthalein

• Blue

Match the following with the correct card for litmus paper

• No change in color

• below 4.5

• Red litmus paper

• 4.5-8.3

• Blue litmus paper

• Above 8.3

Choose the correct statements for colorless phenolpthalein (Choose three)

• Solution could be a base if pH is 7.5

• Solution could be an acid if pH is below 7

• pH is below 8

• Must be a base

Choose the correct statements for pink phenolpthalein (Choose two)

• Could be an acid or base

• pH is from 8-9

• pH is above 9

• Must be a base

Choose the correct statements for red methyl orange (Choose two)

• pH is below 3.1

• pH is from 3.1-4.4

• Must be an acid

• Must be a base

• Could be an acid or base

Choose the correct statements for yellow methyl orange (Choose two)

• pH is above 4.4

• pH is from 3.1-4.4

• Must be an acid

• Must be a base

• Could be an acid or base

What is present in acids and aqueous solutions that can change the color of an indicator? (Choose three)

• hydrogen ions

• hydronium ions when in aqueous solutions

• H₃O+

• hydroxide ions

• OH- ions

What is present in bases and aqueous solutions that can change the color of an indicator? (Choose two)

• hydrogen ions

• hydronium ions when in aqueous solutions

• H₃O+

• hydroxide ions

• OH- ions