Physical Properties of Matter
Fundamentals of Matter
Matter is defined as anything that takes up space. This encompasses everything from the air we breathe to large-scale structures like a skyscraper in a city.
All matter possesses physical properties, which are characteristics that can be observed or measured to describe objects.
Identifying and Observing Physical Properties
Some physical properties are observable through the use of human senses (sight, touch). These include:
Size
Shape
Color
Texture
Hardness
Other properties require specialized tools or specific materials to determine. These include:
Temperature
Mass
Volume
Magnetism
Relative Density (the ability to sink or float in water)
Measuring Properties with Tools and Materials
Volume:
Description: The amount of space a solid, liquid, or gas occupies.
Measurement: Can be measured using a graduated cylinder or by calculating the product of an object's dimensions.
Relationship: Larger amounts of substances correspond to larger volumes.
Mass:
Definition: The amount of matter contained within an object.
Metric Unit: Measured in grams ().
Mass vs. Size: Mass is not inherently tied to the external size of an object. For example, a small iron ball contains more matter and thus has more mass than a large cup made of foam.
Temperature:
Definition: A measure of how hot or cold an object is, reflecting its thermal energy.
Measurement Tool: Thermometer.
Particle Dynamics: When heat is added, particles within an object gain speed and move further apart. Continuous heat addition can cause a state change (e.g., solid to liquid, liquid to gas).
State Change Example (Water):
Heating: Turns water into a gas.
Removing Heat: Turns water into a solid (ice).
Magnetism:
Definition: A pushing or pulling force produced by a magnet.
Testing: Magnetic properties are determined by whether an object is pulled toward or pushed away from a magnet. Only specific materials exhibit magnetic attraction.
Relative Density: Sinking and Floating
Relative Density: This is the scientific method used to determine if an object will sink or float compared to a reference material (usually water).
Observation Rules:
Sink: An object falls to the bottom of the water. This indicates the material is more dense than water.
Float: An object stays on top of the water. This indicates the material is less dense than water.
Application: Understanding relative density helps scientists compare the density of different materials by using water as a standard.
Practical Utility and Material Selection
Selection for Purpose: Choosing materials for projects (such as construction) is based on the specific physical properties required for the environment.
Environmental Adaptation:
Building in tornado-prone areas requires different material properties than building in earthquake-prone areas.
Combining Materials: Materials can be mixed to improve their properties and better suit the needs of a project.
Example: Bricks: Strong bricks are made by combining clay and sand. The clay acts like a glue, binding the parts of the wall together to increase strength.
STEM Career Profile: Interior Designer
Educational Requirement: A Bachelor’s degree.
Compensation: The median salary is listed as $56,040.
Primary Responsibilities:
Designing and furnishing rooms for residential homes and businesses.
Translating customer likes, dislikes, and ideas into aesthetic and functional spaces.
Staying compliant with business laws and the American Disabilities Act (ADA).
Key Skills and Collaboration:
Strong communication and active listening.
Close attention to detail and creativity (innovative designs).
Knowledge of architectural basics.
Collaboration with contractors and plumbers to realize the client's vision.
Questions, Stop and Jots, and Discussion
Think about It (Bowl of Soup):
Q: What physical property do you notice? When you eat food that has just finished being prepared, what do you have to be careful of?
A: One would notice the temperature (heat) and the steam (state change). One must be careful not to burn themselves due to high thermal energy.
Stop and Jot 1: How do you use physical properties to make the soup safe to eat? (e.g., waiting for the temperature to decrease or testing the texture).
Stop and Jot 2: What physical properties can be used to describe a skyscraper? (e.g., size, shape, color, hardness, mass).
Stop and Jot 3: Give examples of matter that can be described using temperature (oven), mass (a weight), and magnetism (a refrigerator door).
Stop and Jot 4: If a ship is made of metal that is more dense than water, then how does it float? (Note: This refers to the overall displacement and shape affecting buoyancy, though the material itself is dense).
Stop and Jot 5: What materials are combined when baking a cake? (e.g., flour, eggs, milk, sugar; combined to change texture and state).
Summarize It - Review Questions:
What physical property should be observed if you were trying to decide what to wear? Answer: B. Temperature.
What physical property is most likely being observed if the materials being used are a paperclip, scissors, and a nail? Answer: C. Magnetism.
What physical property is being tested when determining the relative density of an object or substance? Answer: A. Ability to sink or float.
Fill-in-the-blank: Mass tells how much matter is in an object.
Fill-in-the-blank: Physical properties are characteristics that can be observed or measured.
Relative Density Example: An example of relative density using everyday substances is oil floating on water because oil is less dense than water, or a lead sinker falling to the bottom of a lake because lead is more dense than water.
Virtual Field Trip: Glacier
Observation of a glacier via QR code involves identifying properties such as state of matter (solid), temperature (cold), and color (white/blue).