chapter 2 the properties of matter
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Chapter 2 The Properties of Matter
What is Matter?
Matter and Volume
Matter- Anything that has mass and takes up space. Everything in the universe that you can see is
made up of matter. Volume- The amount of space taken up, or
occupied, by an object. Because objects have volume, they cannot
occupy the same space at the same time.
Liquid Volume
Units for Liquid Volume L mL cm3
Measuring Liquid Volume Use graduated cylinder– more accurate Meniscus – the curve at a liquids surface
Read liquid measurements from the bottom of the meniscus.
Solid Volume
Regularly Shaped Objects Units for solids
cm3 units (having 3 sides)
Volume = length (l) x width (w) x height (h)
Irregularly Shaped Objects Same units as above Use water displacement method.
Submerge object in a known amount of water and read the level change.
1 mL = 1 cm3
Matter and Mass
Mass– the amount of matter in an object. The more matter in the object, the greater the
mass Mass of an object is the same regardless of the
object’s location in the universe. Mass vs. Weight
Mass and weight do NOT have the same meaning. Weight– the measure of gravitational force exerted on
an object. Will change with location in the universe
Difference Between Mass and Weight
MASS Measure of the amount
of matter in an object Always the same
regardless of location in universe
Measured using a balance
Expressed in grams
WEIGHT Measure of graviatational
force on an object Changes based on
location in the universe Measured using a scale Expressed in Newtons
(N)
Inertia
Inertia- the tendency of an object to resist a change in motion. The object will remain at rest until something
causes the object to move. A moving object will continue moving at the same
speed and in the same direction unless something acts on the object to change speed or direction
Mass: The Measure of Inertia
Mass is the measure of inertia An object with a large mass is harder to get
moving and is harder to stop
1.2 Physical Properties A Physical Property of matter can be observed or measured
without changing the matter’s identity. Examples:
color Melting and boiling points mass Conduct electricity Strength Flexibility State – solid, liquid, or gas Density – the amount of mass in a given volume Solubility Ductility – ability to be draw into wires Malleability – ability to be hammered into sheets
Physical Properties
Viscosity - A liquid’s resistance to flow
Malleable– Can be hammered into thin sheets
Density
Density is a physical property that describes the relationship between mass and volume.
Density- the amount of matter in a given space or volume. Basketball vs. bowling ball.
They both are the same size, but the bowling ball has more mass.
Since it has more mass, it has a greater density
Density Continued
Denser liquids go to the bottom of the container. Think of vinegar and oil salad dressing
Density of solids. Would you rather carry 1kg of feathers or 1kg of
lead? The lead would be much smaller to carry around.
An object will float on water if it is less dense that water
The object will sink if it is more dense than water.
Density Continued
To find density, you must first measure the mass and volume of the object.
The formula is: Density = mass D = m
volume V The unit will be g/cm3 . You may also see kg/m3 or
kg/L
Density Continued
What is the density of an object whose mass is 25g and whose volume is 10 cm3?
Suppose you have a lead ball whose mass is 454 g and density is 11.35 g/cm3. What is the volume of the ball?
Density Continued
What is the mass of a 15 mL sample of mercury with a density of 13.55 g/mL?
A graduated cylinder contains 25 mL of water. When a 4.5 g paper clip is dropped into the water, the water level rises to 36 mL. What is the density of the paper clip?
1.3 Chemical Properties Chemical Properties -Describes matter based on its ability
to change into new matter that has ________ properties. Wood is flammable. (Ability to burn) Reactivity- the ability of two or more substances to
combine. Iron combines with water and oxygen to form rust.
Physical Changes
Physical changes do not form new substances. Physical change- A change that affects one or
more physical properties of a substance. Examples include:
silver shaped into jewelry Cutting a piece of wood Tearing a piece of paper Dissolving sugar in water Cutting or braiding hair
Characteristic Properties
Characteristic properties- These properties are always the same no matter what amount you have.
Chemical change- Occurs when one or more substances are changed into new substances that have new and different properties. When you bake a cake, you combine flour, sugar,
eggs, and several other ingredients. The product is the cake. You cannot unbake the cake and return to the original ingredients.
Signs of a Chemical Change Several signs indicate a chemical change has taken
place. These include: Change in color Change in odor production of heat fizzing and foaming, or bubbling or formation of a precipitate (solid)
When you bake a cake you smell it baking, you see it browning, and when you cut it open you can see pockets of gas.
Color Change
Copper will form a patina when exposed to moist air
Production of a Gas
Carbon Dioxide gas forms when baking soda is mixed with vinegar.
Formation of a Precipitate
Curds in cottage cheese form when acid is added to milk
Composition
Composition- The type of matter that makes up the object and the way that the matter is arranged in the object. Physical changes will not change the composition
of the material. Chemical changes will change the composition of
the material.
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