Matter and Energy Chapter 2 Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Section 2.1 Representations of Matter: Models and Symbols Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 1 Identify and explain the difference among observations of matter at the macroscopic, microscopic, and particulate levels. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 2 Define the term model as it is used in chemistry to represent pieces of matter too small to be seen. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Anything that has mass (sometimes expressed Matter: Anything that has mass (sometimes expressed as weight) and takes up space Matter can be observed and/or thought about at different levels: Macroscopic Microscopic Particulate Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Macroscopic samples of matter: Mountains Rocky cliffs Huge boulders Rocks and stones Gravel Sand Macro- means large Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Microscopic samples of matter: Tiny animals or plants Cells Crystals on rock surfaces Micro- means small Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Particulate samples of matter: Too small to see, even with the most powerful optical microscope Chemists imagine the nature of the behavior of the tiny particles that make up matter, and they use that knowledge to carry out changes from one type of macro- or microscopic matter to another Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Macroscopic, microscopic, and particulate matter Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

A representation of something else Model: A representation of something else Geologists model the earth (globe) Biologists model cells Chemists model atoms and molecules Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Ball-and-stick model: Symbolizes atoms as balls and the electrons that connect those atoms as sticks Space-filling model: Shows the outer boundaries of the particle in three-dimensional space Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Models and symbols used to represent particulate matter Ball-and-stick models Space-filling models Chemical formula and Lewis diagram Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Models are represented with symbols Chemical symbols are letters that represent atoms of elements H represents an atom of hydrogen O represents an atom of oxygen H2O represents a molecule of water: Two hydrogen atoms and one oxygen atom Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Macroscopic, particulate, and symbolic forms and representations of matter Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Section 2.2 States of Matter Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 3 Identify and explain the differences among gases, liquids, and solids in terms of (a) visible properties, (b) distance between particles, and (c) particle movement. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

States of matter: Gas The air you breathe Liquid The water you drink Solid The food you eat Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Kinetic Molecular Theory: All matter consists of extremely tiny particles that are in constant motion Kinetic refers to motion Molecular comes from molecule, the smallest individual particle that is present in one kind of matter Theory is a collection of general propositions that, when taken together, explain a class of related natural phenomena Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

The speed at which particles move is faster at higher temperatures and slower at lower temperatures There is an attraction among particles in all samples of matter The state of matter of any sample depends on temperature and the attractions among the particles that make up the sample Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Particles are independent of one another, moving in random fashion Gas Particles are independent of one another, moving in random fashion Liquid Particles move freely among themselves, but clump together Solid Particles vibrate in fixed positions relative to one another Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Physical and Chemical Properties and Changes Section 2.3 Physical and Chemical Properties and Changes Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 4 Distinguish between physical and chemical properties at both the particulate level and the macroscopic level. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 5 Distinguish between physical and chemical changes at both the particulate level and the macroscopic level. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Description by senses—color, shape, odor, etc. Physical Properties: Description by senses—color, shape, odor, etc. Measurable properties—density, boiling point, etc. Charcoal is black Glass is hard The boiling point of water is 100°C Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

New form of old substance No new substances formed Physical Changes: New form of old substance No new substances formed Ice melts Dry ice changes to gaseous carbon dioxide A rock is ground into sand Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

In a physical change, the particles of matter themselves are unchanged Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Old substances destroyed New substances formed Chemical Changes: Old substances destroyed New substances formed Water decomposes to hydrogen and oxygen gases Iron rusts Food is digested Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

When electricity is passed through certain water solutions, the water decomposes into its elements, hydrogen and oxygen. This is a chemical change. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Properties defined by types of chemical changes possible Chemical Properties: Properties defined by types of chemical changes possible Water can be decomposed to its elements Iron will rust under certain conditions Starch molecules react to form sugar molecules during digestion Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Section 2.4 Pure Substances and Mixtures Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 6 Distinguish between a pure substance and a mixture at both the macroscopic level and the particulate level. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 7 Distinguish between homogeneous and heterogeneous matter. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

A single chemical; one kind of matter Pure Substance: A single chemical; one kind of matter Unique set of physical and chemical properties Cannot be separated into parts by a physical change Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

A sample of matter that consists of two or more chemicals Mixture: A sample of matter that consists of two or more chemicals Physical and chemical properties vary as the relative amounts of different parts change Can be separated into parts by physical changes Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

The boiling point of a mixture (solution) changes as the composition Water is a pure liquid and has a constant boiling point (a physical property); The boiling point of a mixture (solution) changes as the composition of the mixture changes Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

A pure substance cannot be distinguished from a mixture of uniform appearance by observation alone at the macroscopic level Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

A sample that has a uniform appearance and composition throughout Solution: A homogeneous mixture Coffee, air, brass Homogeneous: A sample that has a uniform appearance and composition throughout Tea, paint, gasoline Heterogeneous: Different phases, usually visible Carbonated beverages, salad dressings Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Homogeneous pure substances and mixtures Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Separation of Mixtures Section 2.5 Separation of Mixtures Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 8 Describe how distillation and filtration rely on physical changes and properties to separate components of mixtures. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Most natural substances are mixtures; chemists separate mixtures into pure substances Nitrogen and oxygen are purified from the mixture called air Pure water is purified from the mixture called natural water Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Iron and sulfur form a heterogeneous mixture. Magnetism is a physical property: Iron is attracted to a magnet, sulfur is not. This physical property is the basis of the separation of this mixture Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Separation of the parts of a mixture by heating Distillation: Separation of the parts of a mixture by heating a liquid until one component boils to the gaseous state. The pure gas is cooled and collected in the liquid state. Boiling is a physical change; a homogeneous mixture is changed so that at least one component is separated as a pure substance Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Laboratory distillation apparatus Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Separation of the parts of a mixture by Filtration: Separation of the parts of a mixture by using a porous medium, such as filter paper, to separate components based on size Filtration is based on the physical properties of a mixture: the particle sizes of a component must be significantly larger or smaller than the pore size of the filtration medium Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Gravity filtration Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Elements and Compounds Section 2.6 Elements and Compounds Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 9 Distinguish between elements and compounds. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 10 Distinguish between elemental symbols and the formulas of chemical compounds. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 11 Distinguish between atoms and molecules. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Pure substance that cannot be separated Element: Pure substance that cannot be separated into other stable pure substances Atom: Smallest unit particle of an element Compound: Pure substance that can be decomposed by a chemical change into two or more other pure substances Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

a particulate-level model of silver atoms The element silver and a particulate-level model of silver atoms Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

At least 88 occur in nature Elements At least 88 occur in nature Examples: copper, sulfur, gold, silver 11 occur in nature as gases 2 occur as liquids (mercury and bromine) the others occur as solids Name of an element is always a single word; compound names usually two words or a multisyllabic compound word Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Familiar objects that are nearly pure elements Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Familiar objects that are compounds Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Letters that symbolize elements Elemental symbols: Letters that symbolize elements The first letter of the name of the element, written in uppercase, is often its symbol If more than one element begins with the same letter, a second letter written in lowercase is added hydrogen, H oxygen, O carbon, C chlorine, Cl sodium, Na (from natrium) iron, Fe (from ferrum) Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Symbolic representation of the particles of a pure substance Chemical formula: Symbolic representation of the particles of a pure substance A combination of the symbols of all the elements in the substance The formula of most elements is the same as the symbol of the element: helium, He; sodium, Na Other elements exist in nature as molecules; their formulas indicate the number of atoms of the element in the molecule: hydrogen, H2; oxygen, O2 Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

A real or hypothetical particle represented by a chemical formula Formula unit: A real or hypothetical particle represented by a chemical formula Ammonia molecules are real particles with the formula NH3: 3 atoms of hydrogen and 1 atom of nitrogen Barium chloride exists as an orderly, repeating pattern of barium and chlorine, but there is no barium chloride molecule--its hypothetical particle has the formula BaCl2: 2 chlorine atoms and 1 atom of barium Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Law of Definite Composition (also Law of Constant Composition): Any compound is always made up of elements in the same proportion by mass (weight) No matter its source, water is 11.1 parts hydrogen per 88.9 parts oxygen Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

The properties of a compound are different from the properties of the elements that make up the compound You are familiar with water Hydrogen and oxygen are very different from water Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Particulate and macroscopic views of elements and compounds Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Particulate and macroscopic views of elements and compounds Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Particulate and macroscopic views of elements and compounds Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Summary of the Classification System for Matter Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

The Electrical Character of Matter Section 2.7 The Electrical Character of Matter Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 12 Match electrostatic forces of attraction and repulsion with combinations of positive and negative charges. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Electromagnetic force Two of the fundamental forces that govern the operation of the universe are: Force of gravity Electromagnetic force The electromagnetic force plays an important role in understanding chemistry It includes electricity and magnetism Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Region in space where the force is effective Force field: Region in space where the force is effective Electrostatic force: The force of an electrical charge that does not move A charged object exerts an invisible electrostatic force Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Two objects having the same charge, both positive or both negative, repel each other Two objects having unlike charges, one positive and one negative, attract each other Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Matter has electrical properties There forces are responsible for the energy absorbed or released in chemical changes Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Characteristics of a Chemical Change Section 2.8 Characteristics of a Chemical Change Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 13 Distinguish between reactants and products in a chemical equation. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Symbolic representation of the essence of a chemical change Chemical Equation: Symbolic representation of the essence of a chemical change Reactants: Beginning substances Products: Substances formed C + O2 CO2 2 H2O 2 H2 + O2 Reactants Products Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 14 Distinguish between exothermic and endothermic changes. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 15 Distinguish between potential energy and kinetic energy. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

A chemical change that releases energy to its surroundings Exothermic Reaction: A chemical change that releases energy to its surroundings Burning charcoal: C + O2 CO2 + energy Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Endothermic Reaction: A chemical change that absorbs energy from its surroundings Decomposition of water: H2O + energy 2 H2 + O2 Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Energy due to position in a field where forces Potential Energy: Energy due to position in a field where forces of attraction and/or repulsion are present Gravitational potential energy: Position in the earth’s gravitational field Electrical potential energy: Position in an electrical field Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Minimization of energy is one of the driving forces that cause chemical reactions to occur Chemical energy comes largely from the rearrangement of charged particles in an electrostatic field Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

The temperature of an object is related to the average Kinetic Energy: Energy of motion The temperature of an object is related to the average kinetic energy of its particles Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Conservation Laws and Chemical Change Section 2.9 Conservation Laws and Chemical Change Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

the sum of mass plus energy is conserved; The Conservation Law: In any change, the sum of mass plus energy is conserved; they are neither created nor destroyed ∆E = ∆m  c2 Matter is an extremely concentrated form of energy Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

A uranium fuel pellet of this size produces energy equal to the energy that would be produced by burning about one ton of coal Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 16 State the meaning of, or draw conclusions based on, the Law of Conservation of Mass. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Law of Conservation of Mass: In a non-nuclear change, mass is conserved; it is neither created nor destroyed In any ordinary chemical change, Total mass of reactants = Total mass of products Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Goal 17 State the meaning of, or draw conclusions based on, the Law of Conservation of Energy. Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Law of Conservation of Energy: In a non-nuclear change, energy is conserved; it is neither created nor destroyed The energy lost in one form is always exactly equal to the energy gained in another form Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.

Common events in which energy is changed from one form to another Presentation Slides to Accompany Cracolice/Peters Introductory Chemistry: An Active Learning Approach, Third Edition Copyright © 2007 Brooks/Cole, a part of the Thomson Corporation.