Transcript Matter - Properties and Changes

Matter
Properties and Composition
http://z.about.com/d/chemistry/1/0/x/c/transitionmetalsolns.jpg
So What is Matter?
• Anything that occupies space and
has mass
What isn’t mass?
•
•
•
•
Energy
Ideas
Sound
And…
Properties
• Physical Property - any property that
can be observed without transforming
the substance into another substance
mass, color, freezing point
• Chemical Property - any property that
cannot be studied without transforming
the substance into a different
substance
iron rusts, paper burns
Properties
• Intrinsic – does not depend on the
amount of material you have
color, solubility, viscosity, malleability,
boiling point, density
• Extrinsic – depends on the amount of
matter
mass, volume, length
Density
• Property derived from two
measurements, mass and volume
• Density = Mass/Volume
• Will have a unit that contains both mass
and volume such as g/cm3, lb/gal, kg/L
• Does not depend on the size of the
sample
Density
• What is the density of a sample of
metal that has a mass of 34.58 g and
when placed in 15.0 mL of water causes
the level to rise to 22.4 mL?
22.4 mL - 15.0 mL = 7.4 mL
M 34.58 g
D=
=
= 4.7 g/mL
V
7.4 mL
CHM 1010
PGCC
Barbara A. Gage
Changes
• Physical Change - change that does not
transform the substance into another
substance
melting, subliming, dissolving
Changes
• What were the physical changes that
you encountered in activities on Day 2?
Changes
• Chemical Change - change that
transforms the substance into another
substance
burning, oxidation of metal
• http://jchemed.chem.wisc.edu/JCESoft
/CCA/pirelli/pages/cca1NaIHgCl2.html
Chemical Change
From Silberberg, Principles of Chemistry, 2007
CHM 1010
PGCC
Barbara A. Gage
Distinguishing Between Physical and Chemical Change
PROBLEM: Decide whether each of the following process is primarily a
physical or a chemical change, and explain briefly:
(a) Frost forms as the temperature drops on a humid winter night.
(b) A cornstalk grows from a seed that is watered and fertilized.
(c) Dynamite explodes to form a mixture of gases.
(d) Perspiration evaporates when you relax after jogging.
(e) A silver fork tarnishes slowly in air.
SOLUTION:
(a) physical change
(b) chemical change
(d) physical change
(c) chemical change
(e) chemical change