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Matter And Energy

Learn about the different types of matter, properties, states of matter, mixtures, solutions, substances, and chemical reactions in this informative chapter.

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Matter And Energy

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  1. Matter And Energy Chemistry IA: Chapter 2

  2. Chapter 2 Matter and Change

  3. What is Matter? • Matter is anything that takes up space and has mass. • Mass is the amount of matter in an object. • Mass is resistance to change in motion along a smooth and level surface. • Examples

  4. Types of Matter • Substance- a particular kind of matter - pure • Mixture- more than one kind of matter

  5. Properties • Words that describe matter (adjectives) • Physical Properties- a property that can be observed and measured without changing the substance. • Chemical Properties- a property that can only be observed by changing the type of substance.

  6. Properties • Words that describe matter (adjectives) • Extensive Properties- only depends on the amount of matter – mass & volume • Intensive Properties- (Describing matter) only depends on the type of matter, not the amount (Ex: color, texture) • Used to identify a substance

  7. States of matter • Solid- mater that can not flow and has definite volume. • Liquid- definite volume but takes the shape of its container (flows). • Gas- a substance without definite volume or shape and can flow. • Vapor- a substance that is currently a gas but normally is a liquid or solid at room temperature.

  8. States of Matter Definite Volume? Definite Shape? Temp. increase Com-pressible? Small Expans. Solid YES YES NO Small Expans. Liquid NO NO YES Large Expans. Gas NO NO YES

  9. Condense Freeze Evaporate Melt Gas Liquid Solid

  10. States of Matter • There are more • Plasma • high temperature low pressure • electrons separate from nucleus • Most common in the universe • More at very low temp • Bose- Einstein condensate • Quantum superfluids

  11. Another Way to Change States • Pressure • For some substances it will turn solids to liquids • For others it will turn liquids to solids • Silly putty • Will turn gas to liquid- • Compressor in refrigerator and AC

  12. Physical Changes • A change that changes appearances, without changing the composition. • Examples? Bending metal • Chemical changes - a change where a new form of matter is formed. • Also called chemical reaction. • Examples? Burning wood • Not phase changes • Ice is still water.

  13. Mixtures • Made up of two substances. • Variable composition. • Heterogeneous- mixture is not the same from place to place. • Chocolate chip cookie, gravel, soil. • Homogeneous- same composition throughout. • Kool-aid, air. • Every part keeps its properties.

  14. Separating mixtures • Only a physical change- no new matter • Filtration- separate solids from liquids with a barrier • Distillation- separate because of different boiling points • Heat mixture • Catch vapor in cooled area • Chromatography- different substances are attracted to paper or gel, so move at different speeds

  15. Chromatography

  16. Phases • A part of a sample with uniform composition, therefore uniform properties • Homogeneous- 1 phase • Heterogeneous – more than 1

  17. Solutions • Homogeneous mixture • Mixed molecule by molecule • Can occur between any state of matter. • Solid in liquid- Kool-aid • Liquid in liquid- antifreeze • Gas in gas- air • Solid in solid - brass • Liquid in gas- water vapor

  18. Solutions • Like all mixtures, they keep the properties of the components. • Can be separated by physical means • Not easily separated- can be separated without creating anything new.

  19. Substances • Elements- simplest kind of matter • Cannot be broken down into simpler • All one kind of atom. • Compounds are substances that can be broken down by chemical methods • When they are broken down, the pieces have completely different properties than the compound. Salt • Made of molecules- two or more atoms stuck together

  20. Compound or Mixture Compound Mixture One kind of piece- Molecules More than one kind - Molecule or atoms Making is a chemical change Making is a physical change Only one kind Variable composition

  21. Element Compound Mixture Which is it?

  22. Chemical Reactions • Another name for chemical change • When one or more substances are changed into new substances. • Reactants- stuff you start with • Products- What you make • NEW PROPERTIES • Because each substance has its own properties

  23. Indications of a chemical reaction • Energy absorbed or released • Color change • Odor change • Precipitate- solid that separates from solution • Not easily reversed • Only clues not certainty

  24. Chemical symbols • There are 116 elements • Each has a 1 or two letter symbol • First letter always capitalized second never • Don’t need to memorize • Some from Latin or other languages

  25. Chemical symbols • Used to write chemical formulas • Subscripts tell us how many of each atom • H2O • C3H8 • HBrO3

  26. Conservation of Mass • Mass can not be created or destroyed in ordinary (not nuclear) changes. • All the mass can be accounted for. • Mass at the start = mass at end

  27. The Nature of Matter Chemists are interested in the nature of matter and how this is related to its atoms and molecules. Gold Mercury

  28. Describing Matter • The properties of matter are: hardness, texture, shape, temperature, flammability, size, andcolor.

  29. Chemistry & Matter • We can explore the MACROSCOPIC world — what we can see — • to understand the PARTICULATE worlds we cannot see. • We write SYMBOLS to describe these worlds.

  30. A Chemist’s View of Water Macroscopic H2O (gas, liquid, solid) Symbolic Particulate

  31. A Chemist’s View Macroscopic 2 H2(g) + O2 (g) --> 2 H2O(g) Particulate Symbolic

  32. Kinetic Nature of Matter Matter consists of atoms and molecules in _____.

  33. The 3+ Properties of Matter Solid Liquid Gas Plasma 1)Has a definite volume and shape 1) It takes the shape of Its container 1) Has no definite shape Nor volume. 1) Certain particles of Gas are ionized 2) The particles (atoms) are tightly fixed in one position 2) Atoms not as Closely Together, so they are Free to move 2) Atoms move at High Speeds in all directions 2 ) Ex: The stars of The universe - The Sun 3) Particles only vibrate 3)Build up great amounts Of pressure 3) A.K.A. ‘FLUID’ Temperature or Energy Level

  34. STATES OF MATTER • _______— have rigid shape, fixed volume. External shape can reflect the atomic and molecular arrangement. • Reasonably well understood. • _______— have no fixed shape and may not fill a container completely. • Not well understood. • _______— expand to fill their container. • Good theoretical understanding.

  35. OTHER STATES OF MATTER • PLASMA— an electrically charged gas; Example: the sun or any other star • BOSE-EINSTEIN CONDENSATE— a condensate that forms near absolute zero that has superconductive properties; Example: supercooled Rb gas

  36. Physical Properties What are some physical properties? • color • melting and boiling point • odor

  37. Graphite — layer structure of carbon atoms reflects physical properties.

  38. Physical Changes • can be observed without changing the identity of the substance Some physical changes would be • boiling of a liquid • melting of a solid • dissolving a solid in a liquid to give a homogeneous mixture — a SOLUTION.

  39. Chemical Properties and Chemical Change • Burning hydrogen (H2) in oxygen (O2) gives H2O. • Chemical change or chemical reaction — transformation of one or more atoms or molecules into one or more different molecules.

  40. Sure Signs of a Chemical Change • Heat • Light • Gas Produced (not from boiling!) • Precipitate – a solid formed by mixing two liquids together http://www.youtube.com/watch?v=DITY2rXYU-I

  41. Physical vs. Chemical • physical • chemical • physical • physical • chemical • Examples: • melting point • flammable • density • magnetic • tarnishes in air

  42. Physical vs. Chemical • Examples: • rusting iron • dissolving in water • burning a log • melting ice • grinding spices

  43. MIXTURE PURE SUBSTANCE yes no yes no Is the composition uniform? Can it be chemically decomposed? Colloids Suspensions Matter Flowchart MATTER yes no Can it be physically separated? Homogeneous Mixture (solution) Heterogeneous Mixture Compound Element

  44. Types of Mixtures • Variable combination of 2 or more pure substances. Heterogeneous –visibly separate phases Homogeneous – Same throughout

  45. Energy • Mostly covered in physics • Two types • Kinetic • Potential

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