Lab Math CFU

Molarity is a ratio of ________ and ________.

• moles of solvent and liters of solute

• moles of solution and liters of solute

• moles of solute and liters of solution

• moles of solute and liters of solvent

Which of the following is not a unit for Molarity?

• Molar

• mol

• mol/L

• M

What is the correct unit for volume? (mark all that apply)

• V

• L

• mol

• M

• mL

What is the correct unit for amount of solute?

• V

• L

• mol

• M

What is the molar mass of sodium (Na)?

• 11 g/mol

• 23 g/mol

• 1 g/mol

• 3 g/mol

What is the molar mass of table salt (NaCl)?

• 805 g/mol

• 35 g/mol

• 23 g/mol

• 58 g/mol

Concentration of stock solution= 5M

Volume needed = 1000 m L

Concentration of working solution = 0.5 M

What is the volume (mL) needed of the stock?

What is the volume (mL) of diluent?

• 50 mL stock and 950 mL of diluent

• 100 L stock and 900 L of diluent

• 200 mL stock and 800 mL of diluent

• 100 mL stock and 900 mL of diluent

Concentration of stock solution= 5.5M

Volume needed = 0.25 L

Concentration of working solution = 2.0 M

What is the volume (mL) needed of the stock?

What is the volume (mL) of diluent?

• 0.091 mL stock and 249.91 mL of diluent

• 90.91 mL stock and 159.09 mL of diluent

• 687.5 mL stock and 62.5 mL of diluent

• none of these

Final Volume needed = 20 mL

Dilute 1:1000 (blood: water)

What are the volumes (mL) of the blood and the volume of the water?

• 0.2 mL blood and 19.8 mL water

• 0.02 mL blood and 19.98 mL water

• 0.002 mL blood and 19.998 mL water

• 0.0002 mL blood and 19.9998 mL water

Final Volume needed = 45 mL

Dilute 1:15 (blood: water)

What are the volumes (mL) of the blood and the volume of the water?

• 3 mL blood and 42 mL water

• 0.3 mL blood and 44.7 mL water

• 0.03 mL blood and 44.97 mL water

• 30 mL blood and 15 mL water