Mass
This is a unit used to represent mass of an object.
gram (g)
This unit is commonly used to represent liquid volume.
milliliter (mL) or a liter (L)
This is the definition of density.
The amount of mass per unit of volume.
This is the tool for measuring the mass of an object
A triple beam balance
If the mass of a rubber bouncy ball is 15 grams, and its volume is 5 milliliters. It's density is this...
3 g/cm3
This is the definition of mass.
The amount of matter in an object/substance.
This is the definition of volume.
The amount of space an object/substance takes up.
This is a unit used to represent density of an object.
The grams per milliliter (g/mL) or the grams per centimeter cubed (g/cm3)
This is the tool used for measuring liquid volume in milliliters. It is a glass or plastic and has many lines.
What is a graduated cylinder?
If 53 mL of alcohol has a mass of 42 grams. What is the density of rubbing alcohol?
0.79 g/mL
What tool is used to measure the mass of an object?
The triple beam balance
This equation is used to find the volume of a rectangular object.
V = LxWxH (Length x width x height)
What is the density of room temperature water?
1 g/mL
What is a variable in an experiment?
The factor in an experiment that is changed.
A 50 gram cube of aluminum has a density of 2.8g/mL What is its volume?
17.9 cm3
How many milligrams are in 5 grams?
5000mg
A student filled a graduated cylinder to 30mL. The student then dropped a rock into the graduated cylinder. The volume in the graduated cylinder rose to 43mL. What is the volume of that rock.
What is 13cm3
If an object sinks, it tells us this about its density?
The density of the object is greater than 1g/mL.
What is a control in an experiment?
The factor in the experiment that is not changed.
The density of a 5 gram piece of iron is 7.87 g/cm3. What is the density of a 10 grams piece of iron?
7.87 g/cm3
Suzy is measuring the mass of 50 mL of water. The total mass including the 15gram graduated cylinder was 65g. What is the mass of the water?
50 grams
The volume of a milliliter of water would have these dimensions if it were in a cube.
1cm x 1cm x 1cm
A golden-colored cube is handed to you. The person wants you to buy it for $100, saying that is a gold nugget. You pull out your old geology text and look up gold in the mineral table, and read that its density is 19.3 g/cm3. You measure the cube and find that it is 2 cm on each side, and weighs 40 g. What is its density? Is it gold? Should you buy it?
Thus the cube is NOT gold, since the density (5.0 g/cm3) is not the same as gold (19.3g/cm3). You tell the seller to take a hike. You might even notice that the density of pyrite (a.k.a. fool's gold) is 5.0 g/cm3. Luckily you are no fool and know about density!
Why is it important to have Standard Units?
So the ability to replicate data across the world.
So valid and reliable data exists.
You have a rock with a volume of 15cm3 and a mass of 45 g. What is its density?
You have a different rock with a volume of 30cm3 and a mass of 60g. What is its density?
3g/cm3
2g/cm3