Properties of Matter Properties of Solids

Properties of Solids include: Hardness Elasticity Brittleness Malleability Tensile strength Density

What is Hardness? Hardness measures a solid’s resistance to scratching. What is the hardest natural substance? Diamond

What is Elasticity? Elasticity is the measure of a solid’s ability to be stretched and then return to its original size. It also gives objects the ability to bounce and to withstand impact.

What is brittleness? Brittleness measures a material’s tendency to shatter upon impact.

Examples of malleable substances What is Malleability? Malleability measures a solid’s ability to be pounded into thin sheets. Examples of malleable substances

What is Tensile Strength? Tensile strength is a measure of how much pulling, or tension, a material can stand before breaking. It’s an important property of fibers, cables, and girders.

What is density? Density is a physical property that describes the relationship between mass and volume.

The units for density are grams per cubic centimeter (g/cm3)

How big is a cubic centimeter? Volume of a cube = l x w x h If the sides are in cm, then the volume is in cm3. 1 cm3 = 1 milliliter

Because density is a ratio, it will stay the same for a homogeneous substance no matter how large or how small the sample.

Examples: The density of a copper penny is the same as the density of a copper pot. The density of a steel paper clip is the same as the density of a steel screw

What about the density of heterogeneous materials? Are the densities of these pieces of cookie the same? Which has the greatest density?

Is this information useful to us? Density describes how tightly packed the atoms or molecules are in a substance. Is this information useful to us?

Useful densities when fishing: Lead D = 11.3 g/cm3 Depth fishing Wax D = 0.87 g/cm3 Plastic D = 0.95 g/cm3 Fly fishing Water D = 1.0 g/cm3 Fish laughing

Different objects have different densities Objects with different densities will always interact with the least dense on top, most dense on bottom. Which of these is the most dense? Honey = 1.36 g/ml Which of these is the least dense? Veg Oil = 0.75 g/ml

Find the mass of the object Determining Density Step 1: Find the mass of the object

Determining Density STEP 2: Determine Volume We have 2 ways to determine VOLUME. Measure Cube = L * W * H Cylinder = Πr2H Sphere = (4Πr3)/3 Calculate Displacement Displacement is how much liquid is moved out of the way to make room for the object placed in water

Determining Density Step 3: Calculate Density = Mass Volume Units: For ruler: g/cm3 For displacement: g/ml

Manipulating Triangle http://earth2class.org/docs/tchrlessonplans/densitymovie[1].swf

Find the mass of the object Find the volume of the object To find density: Find the mass of the object Find the volume of the object Divide : Density = Mass / Volume Ex. If the mass of an object is 35 grams and it takes up 7 cm3 of space, calculate the density.

Set up your density problems like this: To find density: Find the mass of the object Find the volume of the object Divide : Density = Mass / Volume Ex. If the mass of an object is 35 grams and it takes up 7 cm3 of space, calculate the density. Set up your density problems like this: Known: Mass = 35 grams Unknown: Density (g/cm3) Volume = 7 cm3 Formula: D = M / V Solution: D = 35g / 7cm3 D = 5g/cm3

Practice Problem 1 Osmium is a very dense metal. What is its density in g/cm3 if 50.00 g of the metal occupies a volume of 2.22cm3? 1) 2.25 g/cm3 2) 22.5 g/cm3 3) 111 g/cm3

Practice Problem 2 If blood has a density of 1.05 g/mL, how many milliliters of blood are donated if 575 g of blood are given? 1) 0.548 mL 2) 548.0 mL 3) 1.830 mL

lecturePLUS Timberlake Practice Problem #3 What is the density (g/cm3) of 48 g of a metal if the metal raises the level of water in a graduated cylinder from 25 mL to 33 mL? A) 0.2 g/ cm3 B) 6 g/cm3 C) 252 g/cm3 25 ml 33 mL lecturePLUS Timberlake