Friday, Sept. 20 th : “A” Day Monday, Sept. 23 rd : “B” Day Agenda  Ch 1 Tests  Start Ch. 2: Matter and Energy  Section 2.1: “Energy” Energy, physical/chemical.

Slides:



Advertisements
Similar presentations
Chapter 2 sec 1 Intro Energy.
Advertisements

Energy and Chemical Reactions Energy is transferred during chemical and physical changes, most commonly in the form of heat.
Energy and Chemical Reactions Energy is transferred during chemical and physical changes, most commonly in the form of heat.
Energy and Phases. Potential Energy - stored energy (stored in bonds, height) Kinetic Energy - energy of motion, associated with heat.
Section 3.3 – Phases Changes
Endothermic Reactions (need heat) (Absorb heat energy from their surroundings) Solid + heat  Liquid (Fusion/Melting) Liquid + heat  Gas (Boiling/Evaporation/Vaporization)
Matter and Energy (page 17 of Scientific Notebook)
Aim: How to measure energy absorbed during a phase change
Ch. 11 Thermochemistry.
Just What Is It How Can We Define Energy The capacity to do work Or the ability to cause a change to occur.
The Nature of Energy u Energy is the ability to do work or produce heat. u It exists in two basic forms, potential energy and kinetic energy.
Energy Kinetic energy = energy of motion. Energy Potential energy = stored energy 1. energy of position due to gravity.
States of Matter Solid Lowest energy/heat Molecules barely moving Definite, uniform shape Example: ice.
Changing Matter 2-3.
Energy Chapter 2 Section 1.
CHEMISTRY September 21, Warm Up What is the difference between heat and temperature? Which bench will you sit on when exposed to 120 o F sunlight.
Heat, Energy and Phases of Matter  Energy – ability to do work Work - force x distance Two types of energy  Potential Energy – stored energy ex: stretched.
Matter and Energy When Matter and energy interact changes in matter occur.
Thermochemistry and Energy Water freezing and boiling at the same time, really?!
Bellringer Work in small groups to brainstorm ideas relating to energy. List different types of energy, list why energy is important, and when energy is.
Chapters 13 & 17 Phases and Heat. Phases of Matter Chapter 13.
Part One Heat and Temperature.
The universe is made up of: The system – the thing that you are studying The surroundings- everything else.
Integrated Physics and Chemistry
Energy.
Energy. Energy The capacity to do some kind of work. The capacity to do some kind of work. Involved when there is a change in matter Involved when there.
Matter and Energy.
:. Definition 1 The energy the object has due to its motion.
Chapter 3 Quiz By: Will Saunders & Chris Murray 8 th Block-LaFever-10/9/08.
Chapter 6. Heat Definition: the transfer of energy (thermal) between objects that are at different temperatures. Definition: the transfer of energy (thermal)
Physical Science Mr. Moss RHS.  When 2 states are present at the same time, we describe each as a phase.  Here, we see 2 phases of water: ◦ Solid Phase.
Chapter 2 Section 1 ENERGY. Energy The ability to do work or cause change. (the first part is more a physics idea and the second a chemistry)The ability.
Energy and Phases.  Potential Energy - stored energy (stored in bonds, height)  Kinetic Energy - energy of motion, associated with heat.
Section 1.   Chemical Energy:  Energy that matter possess because of its chemical makeup.  Where does the energy come from?  Movements of the atoms.
Matter and Energy Chapter Energy. Objective/Warm-Up Students will be able to apply their knowledge of density to a real world problem. How can you.
Changes of State Chapter 3 Section 2. Changing State By removing or adding energy, a substance can lose or absorb energy, its temperature can change,
CHAPTER 2  Heat  Temperature and Conversions  Specific Heat.
Energy and Physical Changes Energy is transferred during both chemical and physical changes, most commonly in the form of heat.
Ch 13: Solids and Liquids Ch 13 begins with notes from Ch 3.6 and 3.7 on Energy, Temperature and Heat. We did not do these sections when in Ch 3 as the.
Chemistry—Chapter 2 ENERGY. What is ENERGY? (list types of energy) The ability to do WORK. What is WORK? The ability to move something, create a new compound.
Energy and Chemical Reactions Energy is transferred during chemical and physical changes, most commonly in the form of heat.
Heat and Energy of Ractions Chapter 10 Energy World of Chemistry Zumdahl Last revision Fall 2009.
Thermochemistry. Thermochemistry is the study of heat changes that occur during chemical reactions. Heat (q) - energy that is transferred from one object.
Bellringer What would happen to the particles of a substance if it were cooled to absolute zero? In other words, how would they behave? 2.Do.
Changes of State also known as Phase Changes. What are phase changes? Phase changes (changes of state) are the processes of changing from one state of.
Chapters 13 & 17 Phases and Heat. Phases of Matter Chapter 13.
Phase Changes.  A PHASE CHANGE is a reversible physical change that occurs when a substance changes from one state of matter to another  The temperature.
Energy Changes & Phase Changes Heating & Cooling Curves.
Chapters 13 & 17 Phases and Heat. Phases There are three phases, or states, that we will discuss  Solid  Liquid  Gas.
Phase Changes Slide Show #2. Skip #1 & #2 We’ll get to these later.
Chapter 2 Matter and Energy. Energy Energy—the capacity to do work Where does your energy come from? Can be in the forms: light, heat, chemical, mechanical,
Energy, Temperature, and Kinetic Energy. States of matter Solids  fixed volume and shape  particles are held tightly in place  particles vibrate slightly.
Heat and Energy of Ractions Chapter 10 Energy World of Chemistry Zumdahl Last revision Fall 2009.
ENERGY. Energy Ability to do work Kinetic Energy Energy of motion Potential Energy Stored energy Temperature Measure of the Average Kinetic Energy of.
Changes of State Solid, Liquid, Gas, Plasma, Bose- Einstein Condensate.
Ch. 17 Thermochemistry and Energy A liquid freezing and boiling at the same time, really?!
Just What Is It How Can We Define Energy The capacity to do work Or the ability to cause a change to occur.
Thermochemistry Thermo = heat Chemistry = study of matter.
Phase Changes Physical Science
Unit: ENERGY Topic 1: Types of Energy Energy = The ability to do work or produce heat Unit of energy = the Joule = J Two types: Potential Kinetic Lord.
Heat and Energy of Ractions Chapter 10 Energy World of Chemistry Zumdahl Last revision Fall 2009.
Energy!. Energy What do you feel like when you have no energy? What do you really not want to do? –Being lazy and doing no work! Energy: The ability to.
Chapter 2 Section 1 Energy Objectives
Ch 2 Matter and energy Energy and change
Is the process by which the substance changes from solid to liquid.
Ch 2 Matter and Energy When ice melts- what happens to its chemical composition?? Name a source of energy for your body. Name some temperature scales.
CHANGES OF STATE.
Changes of State Chapter 3 Section 3.
How are various forms of energy different?
Endothermic vs Exothermic Reactions
Presentation transcript:

Friday, Sept. 20 th : “A” Day Monday, Sept. 23 rd : “B” Day Agenda  Ch 1 Tests  Start Ch. 2: Matter and Energy  Section 2.1: “Energy” Energy, physical/chemical changes, evaporation, exothermic/endothermic, law of conservation of energy  Homework: Pg. 45: #1-13 Phase Change Diagram WS Concept Review: “Energy” **Quiz over section 2.1 next time!**

Ch 1 Tests “The Science of Chemistry” ClassAverage Score (out of 60) Percentage 2A 4A 1B 3B

Ch 2: Matter and Energy Sec. 2.1: “Energy”  Energy: the capacity to do work, such as moving an object, forming a new compound, or generating light.  Energy is always involved when there is a change in matter.

Changes in Matter can be Physical or Chemical  Physical change: a change of matter from one form to another without a change in chemical properties.  The chemical nature of the substance does not change. Examples: Ice melting Water boiling

Changes in Matter can be Physical or Chemical  Chemical change: a change that occurs when one or more substances change into entirely new substances with different properties.  A chemical change occurs whenever a new substance is made. Example: Reaction of hydrogen + oxygen to produce water +

Every Change in Matter Involves a Change in Energy  All physical AND chemical changes involve a change in energy.  Sometimes, energy must be supplied for the change in matter to occur. Example: for ice to melt, energy must be supplied so that the particles have enough energy to slide past one another

Every Change in Matter Involves a Change in Energy  If more energy is added to the melted ice and the boiling point is reached, the particles of the liquid will leave the liquid’s surface through evaporation.  Evaporation: the change of a substance from a liquid to a gas.

Energy and Change  Sometimes, energy is released when a change in matter occurs. Examples: Energy is released when a vapor turns into a liquid (condensation) Energy is released when a liquid turns into a solid (freezing) Energy is released when hydrogen and oxygen combine to form water

Endothermic/Exothermic Processes  Endothermic: describes a process in which heat is absorbed from the environment Examples Ice melting Water boiling

Endothermic/Exothermic Processes  Exothermic: describes a process in which a system releases heat into the environment Examples Water freezing Water condensing into liquid from vapor Hydrogen + oxygen form water

Conservation of Energy  Law of conservation of energy: the law that states that energy cannot be created or destroyed but can be changed from one form to another.  During any chemical or physical change, the total quantity of energy remains constant.

Energy is Often Transferred  To keep track of energy changes, chemists use the terms system and surroundings.  System: all of the components that are being studied at any given time  Surroundings: everything outside of the system

Conservation of Energy in a Chemical Reaction  An exothermic process involves a transfer of energy from a system to its surroundings.  An endothermic process involves a transfer of energy from the surroundings to the system.  The total energy of the systems and their surroundings remains the same.

Conservation of Energy in a Chemical Reaction Does this chart represent an exothermic or endothermic process?

Energy Can be Transferred in Different Forms  The transfer of energy between a system and its surroundings can involve different forms of energy: Chemical Mechanical Light Heat Electrical Sound

Heat  Heat: the energy transferred between objects that are at different temperatures; energy is always transferred from higher-temperature objects to lower-temperature objects until thermal equilibrium is reached.  Kinetic energy: the energy of an object that is due to the object’s motion

Energy Can be Released or Absorbed as Heat  Exothermic reaction Energy is released as heat  Endothermic reaction Energy is absorbed as heat

Heat is Different From Temperature  Temperature: a measure of how hot or cold something is; specifically, a measurement of the average kinetic energy of the particles in an object.

Temperature is Expressed Using Different Scales  The two temperature scales that are used in chemistry are: Celsius, ˚C Kelvin, K  0˚C = freezing point of water  0 K = absolute zero, the temperature at which the minimum average kinetic energies of all particles occur

To find °C = T(K) To find K = t(˚C) + 273

Transfer of Heat May Not Affect Temperature Heating Curve for Water

Transfer of Heat May Not Affect Temperature  Notice that the temperature only increases when the substance is in the solid, liquid, or vapor states.  The temperature does not increase when the solid is changing to a liquid or when the liquid is changing to a gas.  The energy that is added is used to change state.

Specific Heat  Specific Heat: the quantity of energy, as heat, that must be transferred to raise the temperature of 1 g of a substance 1 K or 1˚C.  The SI unit for energy is the joule (J)  Specific heat is expressed in: joules per gram kelvin (J/g · K)

Specific Heat  Metals tend to have low specific heats, which indicates that relatively little energy must be transferred as heat to raise their temperatures.  Water has an extremely high specific heat.  This is why a metal pot gets hot fast but the water inside it takes a long time to warm up.

Specific Heat  This is also why Lake Michigan is always so cold, even in August!  It takes a long time to warm something, like water, that has a high specific heat.

Homework  Section 2.1 review, pg. 45: #1-13  Phase Change Diagram worksheet  Homework: Concept Review: “Energy” **Next time: Sec 2.1 Quiz**