1 / 34

Matter and Energy An Introduction Still Another View

Matter and Energy An Introduction Still Another View. What is Matter?. Matter Anything that occupies space and has mass Atoms Tiny particles too small to see Molecules Atoms bonded together- also too small to see. Classifying Matter. States of Matter Solid Fixed Volume Rigid Shape

rayya
Download Presentation

Matter and Energy An Introduction Still Another View

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. Matter and EnergyAn IntroductionStill Another View

  2. What is Matter? • Matter • Anything that occupies space and has mass • Atoms • Tiny particles too small to see • Molecules • Atoms bonded together- also too small to see

  3. Classifying Matter • States of Matter • Solid • Fixed Volume • Rigid Shape • Liquid • Fixed volume • Assume the shape of the container • Gas • Atoms separated by large distances • Assume the volume and shape of the container

  4. Classifying MatterBased on Composition Pure substance • Matter that has a uniform and unchanging composition Mixture • Two or more substances physically placed together in any proportion; each retains its characteristic properties

  5. Classifying Matter • Mixtures • Heterogeneous Mixture • Two or more regions with different composition • Homogeneous Mixture • Uniform composition • Elements • Cannot be broken into simpler substances • Compounds • Composed of two or more elements

  6. Classifying Matter

  7. Classifying Matter • Matter • Pure substance • Element • Compound • Mixture • Heterogeneous • Homogeneous

  8. Physical and Chemical Properties • Physical properties • No change of composition • Chemical properties • Change of composition

  9. Physical and Chemical Properties • Physical properties • Boiling point • Odor • Taste • Color • Melting point • Density

  10. Chemical properties • Oxidation  Rust • Flammability • Chemical activity

  11. Matter and EnergyConservation of Mass • Antoine Lavoisier • Law of Conservation of Mass • “Matter is neither created nor destroyed”

  12. Conservation of Mass • Total amount of matter remains constant in a chemical reaction • 58 grams of butane burns in 208 grams of oxygen to form 176 grams of carbon dioxide and 90 grams of water. 58 grams + 208 grams = 176 grams + 90 grams 266 grams = 266 grams

  13. Energy • Energy • Law of Conservation of Energy • “Energy is neither created nor destroyed”

  14. Energy • Energy • Capacity to do work- what does this mean? • Types of Energy • Kinetic Energy – motion • Potential Energy – position • Electrical Energy – flow of electrons • Chemical Energy – chemical changes • Units of Energy • Joule (J) • Calorie (cal)

  15. Conversion of Energy Units A candy bar contains 225 Cal of nutritional energy. How many joules does it contain? Given: 225 Cal Find: J Conversion Factors: 1000 calories = 1 Cal 4.184 J = 1 calorie Solution Map: Cal  cal  J 225 Cal X 1000 cal X 4.184 J = 9.41 X 105 J 1 Cal 1 cal

  16. “flow” ceases at thermal equilibrium EOS Heat (q) Heat is a common form of energy associated with the energy transfer that results from thermal differences between objects or between the system and its surroundings Heat gained q and change in T are positive Heat lost q and change in T are negative “flows” spontaneously from higher Tlower T

  17. Temperature Changes • Heat Capacity • Quantity of heat energy required to change the temperature of a given amount of substance by a standard increment. • Specific Heat Capacity • Amount of substance = exactly 1 gram • T = exactly 1 degree • Units of heat in joules or calories • Can be used to identify materials

  18. Many metals have low specific heats. The specific heat of water is higher than that of almost any other substance.

  19. Calorimeter- Student Style

  20. Calculations • Specific Heat • Used to quantify relationship between heat added and the temperature change • Equation Heat = Mass X Heat Capacity X Temperature Change q = m X C X T

  21. Suppose that you are making a cup of tea. How much heat energy will be needed to warm 236 grams of water (about 8 ounces) from 25 0C to 100 0C ? Given: 235 grams of water  m 25 0C  initial temperature  Ti 100.0 0C  final temperature  Tf Find: Amount of Heat needed  q Equation: q = m X C X T Solution Map: C, m, T q

  22. Equation: q = m X C X T Solution Map: C, m, T q C = 4.18 J/g 0C m = 235 grams T = 100.0 0C – 25 0C = 75 0C q = m X C X T = 235 g X 4.18 J/g 0C X 75 0C = 7.4 X 104 J

  23. A chemistry student finds a shiny rock that she suspects is gold. She weighs the rock on a balance and obtains the mass, 14.3 g. She then finds that the temperature of the rock rises from 25 0C to 52 0C upon absorption of 174 J of heat. Find the heat capacity of the rock and determine if the value is consistent with the heat capacity of gold. Given: m = 14.3 g q = 174 J T = 52 0C – 25 0C = 27 0C Find: C Equation: q = m X C X T Solution Map: m, q, T C

  24. q = m X C X T C = q m X T = 174 J 14.3 g X 27 0C = 0.45J g 0C

  25. Conceptualizing an Exothermic Reaction Surroundings are at 25 °C Typical situation: some heat is released to the surroundings, some heat is retained by the solution. T increases 35.4 °C 32.2 °C 25 °C In an isolated system, all heat remains in the system. Maximum temperature rise. Hypothetical situation: all heat is instantly released to the surroundings. Heat = qrxn

  26. Heat Capacity of Water • Water • High Heat Capacity • Changing water temperature requires a lot of heat energy • Important property for living organisms

  27. Matter and EnergyChapter in Review • Matter • Classification of Matter • Properties and Changes in Matter • Conservation of Matter • Energy • Heat Capacity • Specific Heat Capacity

  28. Matter and EnergyChemical Skills • Classify Matter • Physical and Chemical Properties • Chemical and Physical Changes • Conservation of Mass • Conservation of Energy Units • Energy, Temperature Change, and Specific Heat Capacity Calculations

More Related