physical and chemical changes. physical property: a characteristic of that can be measured without...
TRANSCRIPT
![Page 1: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/1.jpg)
Physical and chemical changes
![Page 2: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/2.jpg)
• Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance.
• Ex. Color, shape, size, density, melting point, boiling point, hardness, conductivity, malleability, ductility, state
![Page 3: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/3.jpg)
Slide 8 of 10
![Page 4: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/4.jpg)
• Physical change: a change which does not change the identity of the substance
• Ex. Boiling, melting, changing shape, mixing, freezing, dissolving
![Page 5: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/5.jpg)
• Chemical change: A change where a new substance is formed from other substances, and has new properties
• Burning O2 and H2 gives off H2O and energy
![Page 6: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/6.jpg)
• Chemical property: A characteristic of a substance which indicates whether it can undergo a specific chemical change
• Ex. Flammability, reactivity, or non-reactivity
![Page 7: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/7.jpg)
Signs of a Chemical Change
• color change, • formation of a
precipitate, • gases given off, • energy change-
heating up or cooling down, light,
![Page 8: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/8.jpg)
Signs of a reaction
• Precipitate: substance formed when a solid forms out of two liquids
![Page 9: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/9.jpg)
Energy change
• Endothermic: chemical reaction that absorbs energy or heat
• Exothermic: chemical reaction gives off energy or heat
![Page 10: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/10.jpg)
Exo vs. endo
![Page 11: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/11.jpg)
Law of conservation of mass
• Law of Conservation of mass: mass of all substances before a chemical reaction is equal to the mass of all substances after the reaction
![Page 12: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/12.jpg)
• •Extensive physical
• –Depend on the amount of the material present (ex. mass, length, & volume)
• •Intensive physical
• –Does not depend on the amount of material present (ex. density, boiling point, ductility, malleability, color)
![Page 13: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/13.jpg)
Boiling Point
• Boiling point- Temperature at which vapor pressure overcomes atmospheric pressure.
• Does Water always boil at 100ºC
• Why or why not?
• What would it do in space?
![Page 14: Physical and chemical changes. Physical Property: A characteristic of that can be measured without changing the chemical composition of a substance. Ex](https://reader036.vdocuments.us/reader036/viewer/2022062518/56649f335503460f94c5040d/html5/thumbnails/14.jpg)