What are Properties used to describe parts of the car?
Some Physical Properties HardnessOdor ColorTexture DensityState of matter Strength Flexibility (malleable, ductile) Shape Melting point, boiling point Ability of conduct electricity
What is a physical property? Any characteristic that can be used to describe matter Often very easy to observe
Melting/Boiling/Freezing points The temperatures when an object changes it’s state of matter
Definitions of Melting, Boiling, Freezing points Boiling point: the temperature at which a liquid becomes a gas, or vice versa Melting point: the temperature at which a solid becomes a liquid Freezing point: same as melting point, but used when the temperature is cooling (decreasing)
Instances, examples What is freezing point of water? What is the boiling point of water?
The numbers Freezing point: 32°F or 0°C Melting point: 212°F or 100°C How to convert Fahrenheit to Celsius: C=5(F-32)/9 1.Begin by subtracting 32 from the Fahrenheit number. 2.Divide the answer by 9. 3.Then multiply that answer by 5. Here's an example: Change 95 degrees Fahrenheit to Celsius: 95 minus 32 is 63. Then, 63 divided by 9 is 7. Finally, 7 times 5 is 35 degrees Celsius.
Possible evidence of physical change Alteration of any physical feature – Length – Shape – Color Application of force which changes the object – Pounding – Tumbling – stretching
Changes in matter Physical Change 1.Does not change a substance identity (chemical makeup, formula) 2.Does change at least one physical property 3.Dissolving is a physical change 4.Changing the state of matter is a physical change 5.Separation of a mixture into its ingredients is a physical change
Examples of physical changes in matter Hair Cut Breaking Chalk Crushing an aluminum can
Definition of chemical property A property of matter that describes the substance’s ability to participate in chemical reactions A chemical property describes how a substance interacts with the materials in the surrounding environment to form new compounds or elements.
Examples of Chemical properties Reactivity Sulfuric acid and Sugar Flammability Carbon Compounds in wood, oxygen in the air and an igniter
Chemical change Occurs when 1 or more substances react to form new substances with different properties Chemical Properties can only be detected when a change occurs Chemical changes can be detected Chemical changes cannot be reversed by physical changes Compounds can be broken down through chemical changes
Possible evidence of chemical change… Change in texture Change in smell Something bubbles or fizzes Changing color
Chemical change CO 2 Gas made by combining Sodium Bicarbonate (NaHCO 3 ) and water (H 2 O)
Results when combining baking soda and with vinegar Vinegar and baking soda chemically react, creating new compounds: CO 2 (g) + NaC 2 H 3 O 2 (aq) (sodium acetate)
Chemical reactions Magnesium reaction with water
Elements with non reactive properties Gold Argon Gas in Light Bulb
Galvanized steel is steel coated with zinc Not galvanized Galvanized nails
Another use for non-reactive materials Dentures, False Teeth, Replacement teeth made from acrylic plastic. Nontoxic, hard, water proof, unreactive, and affordable
Comparing Physical and Chemical properties 1.You can observe physical properties with no visual change substance (the car is red) 2.Observation of chemical properties only occurs when the substance changes (the car is rusting) 3.A physical change in a material does NOT require a change to its chemical identity. A chemical change does
List a Physical and Chemical property of various materials below: SubstancePhysical PChemical P Helium Wood Baking Soda Powdered Sugar Iron Water