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    Energy Energy Presentation Transcript

    • Energy Changes 1 Energy—What is energy?• Energy - the ability to cause change or movement• Examples: • energy can change the temperature of a pot of water • energy can change the direction and speed of a baseball. • https://www.youtube.com/watch?v=_uLSFigtLKg
    • Energy• Word “energy” comes from Greek “energos” which means “active”• Energy is the ability to cause change – Can cause a physical change (state of matter) – Can allow a chemical reaction to occur • Change in the arrangement of atoms in a molecule
    • Energy Changes 1 Energy—What is energy?Examples: continued • energy in a thunderstorm produces lightning and thunder • energy can change the arrangement of atoms in molecules and cause chemical reactions to occur
    • Energy Changes 1 Forms of Energy• Energy comes in different forms from a variety of sources. • chemical energy in the form of food energy • nuclear energy contained in the nucleus of the atom to produce electricity
    • Types of energy• Kinetic and potential (mechanical)All energy is kinetic or potential but there are different kinds of kinetic and potential energy 1. Electrical (movement of electrons) 2. Electromagnetic (light/radiation energy) 3. Chemical (energy in chemical bonds) 4. Thermal (heat) 5. Nuclear (energy stored in atoms) 6. Sound energy
    • Kinetic energy• The energy an object has due to its motion• The amount of kinetic energy of an object depends on its speed and mass – What is speed _____________________________ – What is mass _____________________________• Higher speed or higher mass = more kinetic energy• https://www.youtube.com/watch?v=4CWlNoNpXCc
    • Energy Changes 1 Energy Transformations• An energy transformation occurs if energy changes from one form to another.• Example:• energy stored in the chemical compounds in your muscles changes to energy of motion
    • Energy Changes 1 Energy Transformations: continued• a car sits in sunlight all day, the energy in sunlight (radiant energy) changes to heat energy that warms the inside of the car• energy used to stretch and move a rubber band changes into heat energy that raises the temperature of the rubber band• During energy transformations: • the total amount of energy stays the same • energy is never lost or gained—it only changes form
    • Energy Changes 1 Using Energy Transformations• An electric current in a wire has electrical energy that can be used in many ways.Example: A light bulb converts electrical energy into heat and light energy when you flip on a switch.
    • Energy Changes 1 Kinetic Energy (KE)• kinetic (kih NE tihk) energy (KE) - the energy an object has due to its motionExamples of kinetic energy (KE):• a moving ball due to its motion• a football thrown by a quarterback• a sky diver or a leaf falling toward Earth
    • Energy Changes 1 Mass, Speed, and Kinetic Energy (KE)• moving objects have kinetic energy (KE)• not all moving objects have the same amount of kinetic energy• amount of kinetic energy (KE) an object has depends on the mass & speed of the object• Example:• Mass: a small rock and a large boulder rolling down a hill at the same speed • the large boulder could cause more damage – the large boulder has more kinetic energy • larger the mass of the object the more kinetic energy (KE)
    • Energy Changes 1 Mass, Speed, and Kinetic Energy (KE)Example:Speed: The faster a bowling ball moves, the more pins it can knock down - the more kinetic energy (KE) it has• kinetic energy (KE) increases as speed increases• https://www.youtube.com/watch?v=-dpBVtAbKJU
    • Energy Changes 1 Transferring Kinetic Energy (KE)• Kinetic energy (KE) can be transferred from one object to another when they collide.• Example • Even if the bowling ball does not touch all of the pins, it still can knock them all down with one roll. • The bowling ball transfers kinetic energy (KE) to a few pins. • These pins transfer the kinetic energy (KE) to the remaining pins and knock them down.
    • Energy Changes 1 Potential Energy (PE)• The skier has no kinetic energy (KE) when she is standing at the top of the hill.• But as she skis down and moves faster, her kinetic energy (KE) increases. • Gravity pulls the skier down the hill.• When the skier’s position is at the top of the hill, she has a form of energy called potential energy (PE).
    • Potential energy• Energy stored due to an objects location
    • Energy Changes 1 Potential Energy (PE)• Potential energy (PE) - energy that is stored because of an object’s position• http://phet.colorado.edu/sims/energy-skate- park/energy-skate-park_en.jar
    • Potential energy• The potential energy depends on the location of the object and its mass
    • Energy Changes 1 Potential Energy (PE)• By using the ski lift to take her to the top of the hill, the skier increased her potential energy (PE) by changing her position.
    • Energy Changes 1 Increasing Potential Energy (PE)• When you raise an object above its original position, it has the potential to fall.• If it does fall, it has kinetic energy (KE).• To raise an object, you have to transfer energy to the object.• This energy becomes stored as potential energy (PE).
    • Energy Changes 1 Increasing Potential Energy (PE)• If the object were lifted higher, the potential energy (PE) would increase.• The higher an object is lifted above Earth, the greater its potential energy (PE).
    • Energy Changes 1 Converting Potential (PE) and Kinetic Energy (KE)• Kinetic energy (KE) also can be transformed into potential energy (PE). Example:• Suppose you throw a ball straight up into the air.• The muscles in your body cause the ball to move upward when it leaves your hand - an energy transfer• the moving ball has kinetic energy (KE)
    • Energy Changes 1 Converting Potential and Kinetic Energy• As the ball gets higher and higher, its potential energy is increasing.• At the same time, the ball is slowing down and its kinetic energy (KE) is decreasing.
    • Energy Changes 1 Converting Potential and Kinetic Energy• At its highest point, the ball comes to a stop for an instant before it starts to fall downward again. Here all the kinetic energy (KE) the ball had when it left your hand has been converted to potential energy (PE).
    • Energy Changes 1 Converting Potential and Kinetic Energy• As the ball falls downward, its potential energy (PE) is converted back into kinetic energy (KE).• If you catch the ball at the same height above the ground as when you threw it upward, its kinetic energy will be the same as when it left your hand.
    • Energy Changes 1 Energy Changes in Falling Water• Just like a ball falling to the ground, the potential energy (PE) that water has at the top of a waterfall is transformed into kinetic energy as it falls downward.
    • Energy Changes 1 Energy Changes in Falling Water• The kinetic energy (KE) of falling water can be used to generate electricity.• Water backs up behind a dam on a river, forming a lake or reservoir. (PE)• The water near the top of the dam then falls downward. (KE)• The kinetic energy (KE) of the moving water spins generators, which produce electricity.• The potential energy (PE) of the water behind the dam is transformed into electrical energy.
    • Conserving energy• James Joule demonstrated the law of conservation of energy in 1840 – Law states energy can not be created or destroyed, just transferred from one form to another – The total amount of energy in the universe stays the same – Energy is measured in “Jules of work”
    • Energy Changes 1 Conservation of Energy• Example:• Kinetic energy (KE) - converts into heat energy when two objects rub against each other • A book slides across a table - it will slow down and eventually stop • The book’s kinetic energy (KE) isn’t lost. • Its kinetic energy (KE) converted into heat energy as the book rubs against the surface of the table.
    • Energy transformation• Energy transformation- when energy changes from one form to another form – The total amount of energy stays the same, but the type of energy changes• Chemical energy in a battery is changed into kinetic energy
    • Energy transfer• When you raise an object, you use kinetic energy which is transferred into potential energy (because it has the potential to fall)
    • Other energy transfers• A waterfall has potential energy at the top of the waterfall and kinetic as it falls• Can convert the kinetic energy into electrical energy or use the kinetic energy to move other things
    • Energy Changes 1 Following the Energy Trail• Chemical energy in a soccer player’s leg muscles is converted into kinetic energy (KE) when she swings her leg.• When the ball is kicked - kinetic energy (KE) is transferred to the ball• After the ball rolls for a while, it comes to a stop.• As the ball rolled, its kinetic energy (KE) was transformed into heat energy as the ball rubbed against the grass. http://www.youtube.com/watch?v=_uLSFigtLKg
    • What is Electrical Energy?o Energy caused by the movement of electronso Easily transportedthrough power linesand then converted into other forms of energy
    • What is Chemical Energy? o Energy that can be released during chemical reactions. oEnergy stored in chemical bonds.
    • What is Thermal Energy? • The microscopic kinetic energy of atoms and molecules • A measure of how active the atoms and molecules are. • A hot object has excited molecules and atoms that move fast • A cooler object has slower moving molecules and atoms
    • Temperature 2 Measuring Temperature• Temperature - related to the kinetic energy (KE) of all the atoms or molecules in an object (average kinetic energy)• Because atoms or molecules are so small and objects contain so many of them - it is impossible to measure the kinetic energy of each individual atom or molecule• A practical way to measure temperature is to use a thermometer
    • Temperature 2 The Fahrenheit Scale• Fahrenheit scale – • the freezing point of water = 32°F • the boiling point of water = 212°F • The space between is divided into 180 equal degrees • used mainly in the United States
    • Temperature 2 The Celsius Scale• Celsius (SEL see us) temperature scale • the freezing point of water = 0°C • the boiling point of water = 100°C • The space between is divided into 100 equal degrees • used more widely throughout the world
    • Temperature = heat• Temperature and heat are not the same thing – Temperature: measure of how hot something is – Heat: flow of energy from a hotter object to a cooler one• Measuring temperature and heat – Temperature units: degrees Fahrenheit, Celsius, Kelvin – Heat units: Joule, calorie, BTU, kilocalorie
    • Heat• Heat: transfer of energy from one object to another due to a difference in temperature• Heat flows from warmer object to cooler one
    • • Heat transfer doesn’t mean high  temperature (ex heating beaker of ice)   HOT COLD  HEAT      COLD  VERY More HEAT  HOT
    • Heat transfer• Heat flows from hotter objects to colder objects.• Heat flow depends on the temperature difference between objects• Heat is not temperature• There are thermal insulators and conductors
    • More about heat…• Thermal Conductors – Materials through which it is easy to transfer thermal energy – Metals are the best thermal conductors• Thermal insulators – Poor conductors of heat – Air is a good insulator, therefore, many insulating materials have air spaces – Other good insulators are wood, rubber, and ceramic
    • Temperature 2 Heat on the Move• A transfer of energy occurs if there is a temperature difference between two areas in contact.• Heat is always transferred from warm places to cooler ones.• Heat transfers can take place in three ways • conduction • convection • radiation
    • Temperature 2 Heat on the Move• Conduction transfers heat mainly through solids and liquids• Convection transfers heat mainly through liquids and gases• Radiation can transfer energy through space and air
    • Temperature 2 Conduction• Conduction (kun DUK shun) - the transfer of energy by collisions between the atoms in a material. • A spoon in boiling water becomes warmer because its atoms and molecules moved faster • faster particles then collided with slower-moving particles in the colder of the spoon • Kinetic energy (KE) is transferred up the spoon’s handle.
    • Temperature 2 Bumping Along• In a solid, the particles involved don’t travel from one place to another.• They simply move back and forth in place, bumping into their neighbors transferring energy from faster-moving particles to slower-moving ones.• Conduction usually occurs in solids.
    • Temperature 2 Conductors• thermal conductors - materials through which it is easy to transfer energy• Most metals are good conductors of heat.• Metals such as gold, silver, and copper are the best thermal conductors.• Copper is widely available and less expensive than gold or silver.
    • Temperature 2 Insulators• Materials made of plastics also are often good insulators. • If you put a plastic spoon in boiling water, it takes a long time for it to get hot.• Many cooking pans have plastic handles that remain at a comfortable temperature while the pans are used for cooking.
    • Temperature 2 Insulators• thermal insulators - materials that are poor conductors of heat • Clothes and blankets - • poor conductors of heat • heat cannot escape easily from your body by trapping your body heat around you • help keep you warm because they are made of materials that contain many air spaces.• Air is a good insulator.
    • Temperature 2 Convection• Convection (kun VEK shun) transfers heat when particles move between areas that differ in temperature.• most common in gases and liquids• As temperature increases, particles move around more quickly, and the distance between particles increases.• This causes density to decrease as temperature increases.• Cooler, denser material forces the warmer, less dense material to move upward.
    • Temperature 2 Examples of Convection• Sometimes a bird can stay in the air without flapping its wings because it is held up by a thermal.• A thermal • column of warm air that is forced up as cold air around it sinks • a convection current in the air
    • Temperature2 Convection• Some homes are heated by convection.
    • Temperature 2 Examples of Convection• Convection also occurs in liquids.• In a pot of boiling water, the warmer, less dense water is forced up as the cooler, denser water sinks.• Convection currents on a larger scale are formed in oceans by cold water flowing from the poles and warm water flowing from tropical regions.
    • Temperature 2 Radiation• radiation (ray dee AY shun) - the transfer of energy by waves • radiation waves can be visible light waves or types of waves that you cannot see • When radiation waves strike an object - their energy can be absorbed and the object’s temperature rises • Radiation waves can travel through air and even through a vacuum
    • Temperature 2 Radiation Examples:• The Sun transfers energy to Earth through radiation.• Heat is transferred by radiation from the fire and you become warmer. You also can use radiation to cook food.• A microwave oven cooks food by using microwave radiation to transfer energy to the food.
    • Convection, conduction, radiation• Thermal energy passes by conduction, convection, or radiation• Conduction – transfer of heat by direct contact to a solid substance. Example: the transfer of thermal energy from the metal bar to your hand.
    • • Radiation – transfers energy by waves through empty space. Can be visible light or other types of radiation (fex microwave, UV radiation).
    • Heat• Convection – transfer of heat energy between a solid surface and the nearby liquid or gas in motion• May create a convection cell
    • Convection cell• Heat rises, cool air sinks – Why?• What is density?
    • Expansion, contraction• Expansion: as an object is heated up, the atoms are excited and move more quickly. As they move more quickly, they move farther and expand. – If your balloon deflates, heat it up• Contraction: as an object cools, the atoms move more slowly and become closer together. They contract, or take up a smaller space. – Which will be more dense? A heated balloon or cooled one?
    • Examples• Which is conduction, convection, radiation? B A C
    • More on types of energy• Nonrenewable energy – Made from nonrenewable sources (sources that don’t renew themselves as fast as they are consumed) • Nuclear, fossil fuels, natural gas • These are created naturally but take millions of years to form and we use them much more quickly than they form.
    • More on energy• Renewable energy – Made from renewable sources (can be replenished naturally at same rate or faster than they are consumed) • Solar, wind, tidal, wave, hydroelectric, geothermal, bio-fuel • Some renewable sources are not as good as others… – Discuss downside of biofuel
    • • http://www.youtube.com/watch?v=_uLSFigtLKg• http://www.youtube.com/watch?v=qybUFnY7Y8w
    • Section Check1 Question 1What is energy? AnswerEnergy is the ability to cause change. Anobject that has energy can do something ormake something happen.
    • Section Check1 Question 2A book resting on top of a bookshelf has nokinetic energy. It does, however, have _______energy.A. chemicalB. mechanicalC. negativeD. potential
    • Section Check1 AnswerThe answer is D. If the book falls, its potentialenergy will be replaced by kinetic energy.
    • Section Check1 Question 3As the mass of a moving object increases, itskinetic energy _______.A. decreasesB. increasesC. stays constantD. terminates
    • Section Check1 AnswerThe answer is B.
    • Section Check2 Question 1The two most common temperature scales arethe _______ and the _______ scale.A. absolute and KelvinB. Fahrenheit and KelvinC. Fahrenheit and CelsiusD. Kelvin and Celsius
    • Section Check2 AnswerThe answer is C. In science you will alsoencounter the Kelvin scale but it is notcommonly used in everyday temperaturereadings.
    • Section Check2 Question 2Explain how temperature is related to themotion of molecules in a material. AnswerTemperature is a measure of the average valueof the kinetic energy of the molecules in asubstance.
    • Section Check12-2 Question 3 How are temperature and pressure related?
    • Section Check12-2 Answer When air is heated, its molecules move faster and the air expands This makes the air less dense and it rises. As this less dense air rises and exerts less pressure on anything below it. Cooled air becomes denser and sinks as the molecules slow down and move closer together. This cool air exerts more pressure on anything below it.
    • Section Check2 Question 4Heat can move from place to place in differentways. When heat moves from one object toanother as a result of direct contact, the processis known as _______.A. conductionB. convectionC. radiationD. thermal transfer
    • Section Check2 AnswerThe answer is A. An everyday example ofconduction occurs when you pick up a cup ofcoffee and feel the warmth in your fingers.
    • Chemical Energy 3 Chemical Reactions and Energy— What is a chemical reaction?• In a chemical reaction- • compounds - broken down • new compounds - formed
    • Chemical Energy 3 Energy in Reactions• After the hydrogen and oxygen atoms are bound together to form a water molecule, it is difficult to split them apart.• Energy—usually supplied by electricity, heat, or light—is required to break the chemical bonds.
    • Chemical Energy 3 Energy-Absorbing Reactions• Some chemical reactions need a constant supply of energy to keep them going. These reactions absorb energy. A chemical reaction that absorbs heat energy is called an endothermic (en duh THUR mihk) reaction.• Examples: • preparation of food • photosynthesis
    • Chemical Energy 3 Energy-Absorbing Reactions (endothermic chemical reaction)• Chemical reactions occur when sunlight strikes the leaves of green plants. • These chemical reactions convert the energy in sunlight into chemical energy contained in a type of sugar. Oxygen also is produced by these chemical reactions. • When the plant is deprived of sunlight, the reactions stop.
    • Chemical Energy 3 Energy-Absorbing Reactions• This process is called photosynthesis .
    • Chemical Energy3 Energy-Releasing Reactions• Endothermic chemical reactions are usually important because of the compounds the reactions produce.• Other reactions are important because they release energy.• Exothermic (ek soh THUR mihk) reactions are chemical reactions that release heat energy.
    • Chemical Energy3 Energy-Releasing Reactions• When a substance burns, atoms in the substance combine with oxygen atoms in the air.• An exothermic reaction occurs & energy in the form of heat and light is released.• The exothermic reaction that occurs when a material burns by combining with oxygen is called combustion.
    • Chemical Energy3 Rate of Reaction• Chemical reactions can occur at different rates.Examples:• fireworks explode - very fast chemical reaction rate• rust - very slow chemical reaction rate
    • Chemical Energy3 Changing the Rate of Reaction• Two ways to change the rate of a chemical reaction are: • changing the temperature • adding a type of compound called a catalyst • A catalyst (KA tuh list) - a substance that changes the rate of a chemical reaction without any permanent change to its own structure. • enzymes – protein catalysts that control many cell processes in your body
    • Chemical Energy 3 Changing the Rate of Reaction• Enzymes are found throughout your body and are important for growth, respiration, & digestion.
    • Chemical Energy 3 Changing the Rate of Reaction• When you chew a piece of bread, glands in your mouth produce saliva that contains an enzyme (amylase).• The enzyme in saliva acts as a catalyst to help break down starches in food into smaller molecules.
    • Section Check3 Question 1A substance that speeds up a chemical reactionis known as a _______
    • Section Check3 AnswerA catalyst can be added to speed up achemical reaction. A catalyst changes therate of a chemical reaction without anypermanent change to its own structure.
    • Section Check3 Question 2What occurs when a chemical compound isbroken apart?
    • Section Check3 AnswerWhen a chemical compound is broken apart,the bonds between the atoms that make up thecompound are broken.
    • Section Check3 Question 3Where is the energy stored in a compound? AnswerEnergy is stored in the bonds between theatoms. In order to release that energy the bondsmust be broken.
    • Reviewing Main Ideas1 Energy Changes• Energy is the ability to cause change.• Energy can have different forms. Energy can be transformed from one form into another.• Kinetic energy is the energy an object has due to its motion. Kinetic energy increases as the speed of an object increases.• Potential energy is stored energy that increases as an object’s height increases.
    • Reviewing Main Ideas2 Temperature• Temperature is a measure of the average kinetic energy of the particles in a material.• The movement of energy from a warmer object to a cooler one is called heat.• Heat can be transferred by conduction, convection, and radiation.
    • Reviewing Main Ideas3 Chemical Energy• The energy stored in chemical bonds is chemical energy.• Chemical reactions can release or absorb energy. Exothermic reactions are chemical reactions that release energy. Endothermic reactions absorb energy.• Changing the temperature and adding catalysts can change the rate of chemical reactions.
    • Chapter Review Question 1Why does convection usually occur in liquidsand gases, but not in solids?
    • Chapter Review AnswerIn liquids and gases, atoms and molecules arefree to move from place to place. As a result,they can transfer energy by moving from awarmer place to a cooler place in a material. Insolids, atoms and molecules don’t move fromplace to place within the solid.
    • Chapter Review Question 2In an exothermic reaction, heat energy is_______.A. absorbedB. createdC. destroyedD. released
    • Chapter Review AnswerThe answer is D. Exothermic reactions releaseheat energy.
    • Chapter Review Question 3How does the Sun’s energy reach Earth? AnswerThe Sun’s energy reached Earth by radiation.The other forms of heat transfer can’t occurthrough empty space.
    • Chapter Review Question 4One of the reasons the handle of a pan is madeof wood rather than metal is that wood does nottransfer heat as quickly from the hot pan to yourhand. In other words, wood is a poor _______.A. conductorB. coolantC. insulatorD. thermometer
    • Chapter Review AnswerThe answer is A. Wood is a poor conductor ofheat energy.
    • Chapter Review Question 5Chemical energy is a form of which type ofenergy?A. kinetic energyB. nuclear energyC. heat energyD. potential energy
    • Chapter Review AnswerThe answer is D. Chemical energy is a form ofpotential energy that is stored in the bindsbetween atoms in a compound.
    • Standardized Test Practice Question 1Burning is a(n) _______ chemical reaction.A. endothermicB. exothermicC. photosynthesisD. kinetic
    • Standardized Test Practice AnswerThe answer is B. Because heat is released, thechemical reaction is exothermic.
    • Standardized Test Practice Question 2The temperature of a material increases whenthe atoms in the material _____.A. move closer togetherB. move farther apartC. move fasterD. move slower
    • Standardized Test Practice AnswerThe answer is C. When temperature increases,the atoms are moving faster and have morekinetic energy.
    • Standardized Test Practice Question 3As the height of a ball increases, its _____energy increases.A. kineticB. electricalC. heatD. potential
    • Standardized Test Practice AnswerThe answer is D. When the height of an objectincreases, its potential energy increases.
    • Standardized Test Practice Question 4As water falls from the top of a waterfall, whichforms of energy are changing?A. electrical and chemicalB. kinetic and potentialC. kinetic and electricalD. potential and nuclear
    • Standardized Test Practice AnswerThe correct answer is A. Kinetic energy isthe energy of motion.
    • Standardized Test Practice Question 5What determines the kinetic energy of anobject?A. only its massB. only its speedC. both its mass and speedD. both its mass and speed as well as its direction
    • Standardized Test Practice AnswerThe answer is C. Mass and speed are the twofactors you need to know to determine thekinetic energy of an object.
    • Section Check1 Question 1What is energy? AnswerEnergy is the ability to cause change. Anobject that has energy can do something ormake something happen.
    • Section Check1 Question 2A book resting on top of a bookshelf has nokinetic energy. It does, however, have _______energy.A. chemicalB. mechanicalC. negativeD. potential
    • Section Check1 AnswerThe answer is D. If the book falls, its potentialenergy will be replaced by kinetic energy.
    • Section Check1 Question 3As the mass of a moving object increases, itskinetic energy _______.A. decreasesB. increasesC. stays constantD. terminates
    • Section Check1 AnswerThe answer is B.
    • Section Check2 Question 1The two most common temperature scales arethe _______ and the _______ scale.A. absolute and KelvinB. Fahrenheit and KelvinC. Fahrenheit and CelsiusD. Kelvin and Celsius
    • Section Check2 AnswerThe answer is C. In science you will alsoencounter the Kelvin scale but it is notcommonly used in everyday temperaturereadings.
    • Section Check2 Question 2Explain how temperature is related to themotion of molecules in a material. AnswerTemperature is a measure of the average valueof the kinetic energy of the molecules in asubstance.
    • Section Check12-2 Question 3 How are temperature and pressure related?
    • Section Check12-2 Answer When air is heated, its molecules move faster and the air expands This makes the air less dense and it rises. As this less dense air rises and exerts less pressure on anything below it. Cooled air becomes denser and sinks as the molecules slow down and move closer together. This cool air exerts more pressure on anything below it.
    • Section Check2 Question 4Heat can move from place to place in differentways. When heat moves from one object toanother as a result of direct contact, the processis known as _______.A. conductionB. convectionC. radiationD. thermal transfer
    • Section Check2 AnswerThe answer is A. An everyday example ofconduction occurs when you pick up a cup ofcoffee and feel the warmth in your fingers.
    • Section Check3 Question 1A substance that speeds up a chemical reactionis known as a _______
    • Section Check3 AnswerA catalyst can be added to speed up achemical reaction. A catalyst changes therate of a chemical reaction without anypermanent change to its own structure.
    • Section Check3 Question 2What occurs when a chemical compound isbroken apart?
    • Section Check3 AnswerWhen a chemical compound is broken apart,the bonds between the atoms that make up thecompound are broken.
    • Section Check3 Question 3Where is the energy stored in a compound? AnswerEnergy is stored in the bonds between theatoms. In order to release that energy the bondsmust be broken.
    • End of Chapter Summary File
    • More on types of energy• Nonrenewable energy – Made from nonrenewable sources (sources that don’t renew themselves as fast as they are consumed) • Nuclear, fossil fuels, natural gas • These are created naturally but take millions of years to form and we use them much more quickly than they form.