Density What is density l Density is a

Density

What is density? l Density is a comparison of how much matter there is in a certain amount of space.

Which one is more dense? l Demonstration: People in a square l How about this: Which square is more dense? #1 #2

Which one is more dense? #1 #2

What is density? l Density = mass OR volume mass ÷ volume. l Units for density: g cm 3 _g m. L or l Why are these the units for density? ALWAYS REMEMBER UNITS! .

Let’s try a density problem together l Frank has a stapler. It has a mass of 9 g and a volume of 3 cm 3. What is its density? l Frank also has a paper clip. It has a mass of 3 g, and a volume of 1 cm 3. What is its density?

Frank has a stapler. It has a mass of 9 g and a volume of 3 cm 3. What is its density? 9 g ÷ 3 cm 3 = 3 g cm 3 Frank also has a paper clip. It has a mass of 3 g, and a volume of 1 cm 3. What is its density? 3 g ÷ 1 cm 3 = 3 g cm 3

Work on these problems with your neighbor. l Jack has a rock. The rock has a mass of 6 g and a volume of 3 cm 3. What is the density of the rock? _____ l Jill has a pack of gum. The gum has a mass of 8 g and a volume of 2 cm 3. What is the density of the gum? ______

Jack has a rock. The rock has a mass of 6 g and a volume of 3 cm 3. What is the density of the rock? 6 g ÷ 3 cm 3 = 2 g cm 3 Jill has a pack of gum. The gum has a mass of 8 g and a volume of 2 cm 3. What is the density of the gum? 8 g ÷ 2 cm 3 = 4 g cm 3

Now, try these on your own. l Cassie has a watch. It has a mass of 4 g and a volume of 2 cm 3. What is the density of the watch? ______ l Tori has a wallet. It has a mass of 15 g and a volume of 5 cm 3. What is the density of the wallet? ______

Cassie has a watch. It has a mass of 4 g and a volume of 2 cm 3. What is the density of the watch? 4 g ÷ 2 cm 3 = 2 g cm 3 Tori has a wallet. It has a mass of 15 g and a volume of 5 cm 3. What is the density of the wallet? 15 g ÷ 5 cm 3 = 3 g cm 3

Liquid Layers l If you pour together liquids that don’t mix and have different densities, they will form liquid layers. l The liquid with the highest density will be on the bottom. l The liquid with the lowest density will be on the top.

Liquid Layers l Check out this picture. Which layer has the highest density? l Which layer has the lowest density? l Imagine that the liquids have the following densities: ¡ 10 g/m. L ¡ 6 g/m. L 3 g/m. L 5 g/m. L l Which number would go with which layer?

Liquid Layers – Try with your neighbor l Which liquid has the highest density? l Which liquid has the lowest density? l Which liquid has the middle density?

Liquid Layers – Try on your own! l Imagine that the liquids on the right have the following densities: ¡ 15 g/m. L ¡ 3 g/m. L ¡ 7 g/m. L 10 g/m. L 9 g/m. L 12 g/m. L l Match the colors to the correct densities. 3 g/m. L 7 g/m. L 9 g/m. L 10 g/m. L 12 g/m. L 15 g/m. L https: //www. youtube. com/watch? v=4 EMUs. PJt. Coc

Review l What is the formula for density? l What happens if you pour together liquids that have different densities? l Will the liquid on the top have the highest or lowest density? l Will the liquid on the bottom have the highest or lowest density?

Review l What is the formula for density? D = m v l What happens if you pour together liquids that have different densities? They will form layers l Will the liquid on the top have the highest or lowest density? lowest l Will the liquid on the bottom have the highest or lowest density? highest

Super Scientist Question of the Day l Jake has a book, a ruler, and a balance. l How can Jake find the density of the book with the tools he has?