Question

1.Suppose you want to add 100 mL of solvent to a reaction flask. Which piece of glassware shown in Figure 2.4 would be the best choice for accomplishing this task and why?

2. A reaction requires 21.5g of CHCl3. No balance is available, so it will have to be measured by volume. How many mL of CHCl3 need to be taken? (Density of CHCl3 is 1.484 g/mL.)

3. A 25.27-g sample of pure sodium was prepared for an experiment. How many mL of sodium is this? (Density of sodium is 0.97 g/mL.)

4.In a role-playing video game (RPG) your character is a Human Paladin that can carry 115 lb of gear. Your character is carrying 92 lb of gear and a vial of strength potion (which allows you to carry an additional 50.0 lb of gear). If you find a cave filled with mass potions (used for resisting strong winds), after using the strength potion, how many vials can you collect if the vials each contain 50.0 mL of mass potion with a density of 193 g/mL?The vials have negligible mass.

5. A cape is designed for Lady Gaga’s concert with 4560 sequins. If a sequin has a volume of 0.0241 cm3 and the sequins have a density of 41.6 g/cm3, what is the mass in lb and kg of sequins on Lady Gaga’s cape?

6. Will a hollow cube with sides of length 0.50 m hold 8.5 L of solution? Depending on your answer, how much additional so lution would be required to fill the container or how many times would the container need to be filled to measure the 8.5 L?

Answer 1

Ans 2

mass of CHCl3 = 21.5 g

Density of CHCl3 = 1.484 g/mL

Volume of CHCl3 = mass/density

= (21.5 g) / (1.484 g/mL)

= 14.487 mL = 14.5 mL

Ans 3

Mass of sodium = 25.27 g

Density of sodium = 0.97 g/mL

Volume of sodium = mass/density

= (25.27 g) / (0.97 g/mL)

= 26.052 mL = 26.10 mL

Ans 5

volume of a sequin = 0.0241 cm3

volume of 4560 sequins = 0.0241 x 4560 = 109.896 cm3

density = 41.6 g/cm3

mass in kg of sequins on Lady Gaga’s cape

= density x volume

= 41.6 g/cm3 x 109.896 cm3

= 4571.6736 g x 1kg/1000g

= 4.572 kg

mass in lb of sequins on Lady Gaga’s cape

= 4.572 kg x 2.205 lb/kg

= 10.08 lb