2-1 Chemical & Physical PropertiesPresentation Transcript
What is matter?
Matter is anything that has mass and takes up space.
Which of the following sets of measurements are more precise?
2.74 cm 2.743 cm
102.3 g 102 g
0.012 L 0.0002 L
2-1: Chemical & Physical Properties
Distinguish between physical & chemical properties.
Identify the characteristics of a substance.
Differenctiate among physical states of matter.
Matter – anything that has a mass and takes up space.
Law of Conservation of Mass/Matter
- Matter cannot be created or destroyed in an ordinary chemical reaction just rearranged to form different substances
Matter can be described using properties .
EXTENSIVE PHYSICAL CHEMICAL INTENSIVE PROPERTIES
Characteristics of Matter
Characteristics of a substance that can be observed without the production of a new substance.
state or phase
Two types of Physical Properties
Depends on the particular sample
for example: volume, mass, weight, shape, etc…
Depends on the type of matter NOT how much there is
For example: color, melting point, specific heat, density, appearance, etc…
describes how a substance reacts or fails to react with other substances to produce new substances.
Reaction to Acid or Base.
Two Types of Changes
an alteration of a substance that only changes the physical properties of the substance.
* Does not change the chemical composition of the matter!!
a change of the chemical composition of a substance that results in the formation of a new substance
ALWAYS forms a new substance that has different physical and chemical properties than the original substance.
*Also known as a chemical reaction.
Recognizing Chemical Change
Change in Color
Copper turns green.
Production of Gas
Baking soda in vinegar produce CO 2 .
Formation of Precipitate
Any formation of a solid that separates from liquid.
Heat or light given off.
When a physical change in a sample occurs, which of the following does NOT change?
One example of a physical change is
the rusting of iron.
mixing a milkshake.
Kinetic Theory of Matter
All matter is made of tiny particles in constant motion.
Potential Energy (PE)
energy due to the position or condition
at the atomic level: the distance between the particles
closer= lower PE farther = higher PE
Kinetic Energy (KE)
energy due to motion
Faster= higher KE Slower= lower KE
Arranged in orderly pattern Yes Yes Touching, but not tightly packed Yes No Far apart and rarely touching No No State or Phase Particle level picture Particles description Keep Volume? Keep shape? Solid Liquid Gas
Very Low Ice Low Water High Vapor Vibrational only Vibrational & translational Move freely Low Medium High State or Phase Particle Movement Amount PE Amount KE Example Solid Liquid Gas
extraordinary state of matter
consists of high energy particles
electrons are stripped from their nuclei
*Most Abundant State of Matter in the Universe!*
An object that has kinetic energy must be
Characteristics of matter that describe how a substance reacts or doesn’t react to other substances is called
Phase Changes – Changes of State
Adding or removing energy (heat) to a substance causes phase changes
The particles potential energy is increased or decreased.
During a phase change, temperature does NOT change
Melting S Δ L (adding energy)
Freezing L Δ S (removing energy)
*Melting point & freezing point of a substance occur at the same temperature.