DENSITY

Practice Problems and Answers

MGCCC, Perk Learning Lab

TLM

1. What is the density of benzene in grams per milliliter if 5.5L of benzene weigh 4.8kg?

2. The density of air is 1.3 g/L. How many liters of air weigh 2.0 lb?

3. Given a cylinder with diameter of 39 mm and height of 39 mm, and mass of 1.0 Kg, what is it’s density?

4. How many ounces does a 250ml sample of sulfuric acid weigh? (density = 1.30 g/ml)

5. What is the density of the Earth if 1.00 yd³ weighs 22.0 lb? Express your answer in lb/ft³.

6. The density of brass is 8.0 g/ml. A cube of brass 2.0 inches on an edge will weigh how many grams?

7. An unknown substance has a volume of 0.114 L and has a mass of 467g. What is its density in g/mL?

8. The density of Ethanoic Acetic Acid is 1.05 g/cm³. What is the mass in kilograms of a volume of 5L?

ANSWERS

1) D = mass ?D= 4.8Kg x 1000g x 1L = 0.87 g/mL

vol 5.5L 1Kg 1000mL

2) V= m ?g = 2 lb x 453.6 g = 907.2 g

D 1 lb

?V = 907.2g = 907.2g x 1L = 697.8 L

1.3g 1.3g

1L

3)Volume of a cylinder v= P r²h

r = ½ d, r = ½ (39mm) = 19.5 mm

v= P (19.5 mm)²(39mm) = 46589 mm³

? cm³ = 46589 mm³ x (1m)³ x (100cm)³ = 46.5 cm³

(1000mm)³ (1m)³

D = 1 Kg x 1000g = 21.5 g/cm³

46.5 cm³ 1Kg

4) m= vD

?oz = 250ml x 1.3g x 1 oz = 11.5 oz

1 mL 28.35 g

5) ? lb = 22 lb x (1yd)³ = 0.815 lb/ft³

ft³ 1 yd³ (3ft)³

6) Volume of a cube v = s³

? v = (2in)³ x (2.54 cm)³ = 131cm³

(1 in)³

? v = 131 cm³ x 1 mL = 131 ml

1 cm³

m= vD = 131 mL x 8g = 1048g

1 mL

7) D = m = 467g x 1 L = 0.467 g/mL

v 0.114L 1000mL

8) ? v = 5 L x 1000mL x 1 cm³ = 5000cm³

1L 1mL

?m = vD= 5000cm³ x 1.05g x 1 Kg = 5.25 Kg

1 cm³ 1000g