Biotechnology 3.4 HW

Which of the following are mass/volume concentration units?

• mg/mL

• g/mg

• L/mg

• µg/µL

• g/L

What mass of salt is needed to make 50 mL of a 100 µg/mL salt solution? Describe how the solution is prepared.

• 5 mg

• 50 mg

• 0.5 mg

• 10 mg

What is the decimal equivalent of the following percentages? 10%, 15%, 25%, 2%, 1.5%, 0.5%

• 0.02

• 0.1

• 0.15

• 0.25

• 0.015

What mass of gelatin (a protein) is needed to make 0.5 L of a 3% gelatin solution? Describe how the solution is prepared.

• 15 g

• 1.5 g

• 30 g

• 3 g

What mass of sodium hydroxide (NaOH) is needed to make 50 mL of a 125 mM NaOH solution? Describe how to prepare the solution.

• 0.25 g

• 6.25 g

• 62.5 g

• 0.0625 g

What is the chemical equation for the ionization of water molecules?

• H2O → H+ + OH-

• H2O → H2 + O2

• H2O → H3O+ + OH-

• H2O → H+ + O2-

Tags

NGSS.HS-PS1-7

What is the pH of a neutral solution?

• 0

• 7

• 14

• 1

What is the pH of a strong acid?

• 1.5

• 7

• 10

• 14

What is the function of pepsin in the stomach?

• Breaks down starch

• Breaks down protein

• Neutralizes acid

• Increases pH

What is the easiest and fastest way to measure pH in a biotech lab?

• Using a pH meter

• Using pH paper

• Using a thermometer

• Using a hydrometer