Physical Properties (2-2)

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The Properties of Matter
Chapter 2
What is matter? (2-1)
Matter is anything that has
mass and volume.
*Mass and weight are different!*
1
Physical Properties (2-2)
A physical property of matter
can be observed or measured
without changing the matter’s
identity.
examples:
thermal conductivity
(is it a
conductor or insulator)
(solid, liquid, gas, plasma)
state
density
solubility (does it dissolve)
ductility (draw out into wire)
malleability (pound into shapes)
odor, color,
melting point,
boiling point
2
Density is the amount of
matter in a given space, or
volume.
Density = Mass / Volume
D=M
V
Units for density are derived
from mass /volume:
g/cm3
g/mL
kg/m3
3
Practice:
1. Find the density of a
substance that has a mass of
3
45 kg and a volume of 43m .
D = M/V
D = 45 kg / 43 m3
D = 1.05 kg/ m3
2. What is the density of an
object whose mass is 25g and
whose volume is 10 cm3?
D = M/V
D = 25 g / 10 cm3
D = 2.5 g/ cm3
4
A physical change affects one
or more physical properties of a
substance without changing the
identity of the substance.
*the identity of the
substance does not change!
melting, freezing, boiling,
cutting, bending,
dissolving
(see poster)
5
Chemical Properties (2-3)
A chemical property describes a
substance’s ability to participate
in chemical reactions.
(or, ability to change into new
matter)
examples:
flammability (combustibility)
acidity
basicity (alkaline)
reactivity
6
A chemical change is when
substances are changed into
new substances with new
properties.
*identity of matter is
changed!
examples:
soured milk,
rusting nail,
burning wood,
baking cake,
digesting food
(see poster)
(transparency)
7
Evidence of a chemical reaction
includes the following signs:
 producing a gas (bubbling)
 change in color or odor
 change in energy
(gives off heat or takes in heat)
 produces sound or light
8
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