1 / 23

Chemistry

Chemistry. Chemistry is the central science that studies matter and the changes that it goes through!. Matter is ANYTHING that has mass and volume. Mass : the amount of matter in an object. Volume : the amount of space an object occupies.

lucas-barnett
Download Presentation

Chemistry

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chemistry Chemistry is the central science that studies matter and the changes that it goes through!

  2. Matter is ANYTHING that has mass and volume. • Mass: the amount of matter in an object. • Volume: the amount of space an object occupies.

  3. Matter is EVERYTHING except sound or light (both forms of energy) as well as ideas, feelings, thoughts or anything else without mass AND volume!

  4. Classifying matter is the process of grouping things according to their common traits or properties. Example: Why would a person group English peas, asparagus, and lettuce together? Common Properties: They are all green. They are all veggies.

  5. Classifying matter is what chemists do to make sense of the world! • Properties describe matter. • There are two types of properties: physical and chemical

  6. Physical Properties do not involve a change in identity of the substance. • can be observed with the senses (see or smell or feel them) • can be measured without changing the object’s identity • examples: density, color, odor, taste, hardness, boiling & melting & freezing points, conductivity, etc.

  7. Chemical Properties are observed when there IS a change in the identity of a substance! • describes the ABILITY of one substance to react with another and produce something NEW Example: Iron has the ability to rust when oxygen is present. • describes the ability of a substance to NOT react Example:Gold is desirable for jewelry making because it does not react with oxygen to form rust.

  8. Changes in matter often occur. • There are two types of changes: physical and chemical.

  9. Physical Changes • Changes what the substance looks like, but DOES NOT change the substance itself. • The original substance is NOT destroyed. Ask yourself: • Do I still have what I started with? OR • Can I get back what I started with? • If the answer is YES to EITHER question, a physical change is involved.

  10. examples: *cutting wood *breaking glass *boiling water *freezing water *dissolving sugar in water (called solubility)

  11. Chemical changes involve a change in identity of a substance. • one substance has reacted with another substance to produce a NEW substance • the new substance has different properties (it looks different and reacts differently)

  12. examples: *exploding or anything to do with fire (flammability or combustion) *rotting/decomposing *digesting *neutralization of stomach acid by pepto-bismol

  13. Word/Phrase Clues to Chemical Changes: • Reacts with • Produces • Forms • Decomposes • Neutralizes • Synthesizes • Combustion & flammability Any word/phrase that indicates the formation of a new substance is a CHEMICAL CHANGE.

  14. Evidence that a chemical change has occurred: • Bubbles (gas) formed • Color change (can be physical – so be careful) • Forms a solid (called a precipitate) • Temperature change (can be physical – so be careful) • Releases odor

  15. The state of matter is the form in which the matter is naturally found based on temperature and pressure.

  16. Solids • have definite shape and definite volume • the particles in it are closely packed together • particles vibrate • High intermolecular attraction/forces among the particles in the solid (this is why they are close together – they are attracted to each other)

  17. Liquids • takes on shape of container • form of matter that “flows” because of less intermolecular attraction • particles are closely packed, but less organized, and move around more freely

  18. Gases • have NO definite shape or volume • expand to fill container • easily compressed • particles are very far apart and fast moving • low/weak intermolecular attraction (not attracted to each other – so far apart)

  19. Plasma • Not found naturally on Earth EXCEPT in lightning bolts. • Found elsewhere in the sun and stars.

  20. What is a state change • A state change means a substance has changed from one state of matter to another. • Example: Water freezing involves a change from the liquid state of matter to the solid state of matter. We can show this as: H2O (l)  H2O(s)

  21. So . . . • Are state changes physical or chemical changes? • PHYSICAL!! • Why? • When the water is in liquid form it is H2O (water). When it is in the solid form as ice, it is STILL H2O (water). The identity of the substance did NOT change! H2O (l)  H2O (s) ALL STATE CHANGES ARE PHYSICAL!

  22. Finished! Finally! 

More Related