Chemistry – Unit 1.2 Worksheet 3

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Chemistry – Unit 1.2 Worksheet 3
Name
Date
Block_______
Chemistry – Unit 1.2 Worksheet 3
More Density Problems
Directions: Show all work, using the factor-label method when possible. Remember that density is the
relationship between mass and volume. Density should be used as a conversion factor between mass and
volume. Make sure you have units with every number and think about significant figures for your final answer.
Example 1: If the density of 45.0 mL block of unknown material is 0.65 g/mL calculate the block’s mass. HINT: Start with what you know about the block (the volume) and use the density as a conversion factor to find
what you are looking for (the mass).
45.0 mL
× 0.65 g
= 29.25 g = 29.5 g (3 Sig Figs)
1 mL
Example 2: A lead cylinder has a mass of 2.43 grams and a density of 2.70 g/ml. Calculate the volume of the lead cylinder. HINT: Start with what you know about the cylinder (the mass) and use the density as a conversion factor to find
what you are looking for (the volume).
2.43 g
× 1 mL
= 0.9 mL = 0.900 mL (3 Sig Figs)
2.70 g
1. Calculate the mass of a liquid with a density of 2.5 g/mL and a volume of 15 mL.
2. Calculate the volume of a liquid with a density of 5.45 g/mL and a mass of 65 g.
3. What is the mass of ethanol that would exactly fill a 200.0 mL container? The density of ethanol is 0.789
g/mL.
4. What volume of silver metal will have a mass of exactly 2500.0 g. The density of silver is 10.5 g/cm3.
5. Find the mass of 250.0 mL of benzene. The density of benzene is 0.8765 g/mL
6. A carver begins work on the following block of granite that weighs
2700 g. What is the density of the granite?
7. A graduated cylinder has a mass of 50 g when empty. When 30 mL of water is added, the graduated
cylinder has a mass of 120 g. If a rock is added to the graduated cylinder, the water level rises to 75 mL and
the total mass is now 250 g. What is the density of the rock?
8. A student performs an experiment with three unknown fluids and obtains the following measurements:
Fluid A: m = 2060 g, V = 2000 mL
Fluid B: m = 672 g, V = 850 mL
Fluid C: m = 990 g, V = 1100 mL
Draw (and label) how the fluids would be layered when poured into a beaker.
9. Use your density skills to find the identity of the following mystery objects.
10. We have discussed two ways to calculate the volume of an object. We have calculated the volumes of both
regular and irregular shaped objects. Describe both techniques using detailed procedures.