Chapter 1 Energy and Matter

Chapter 1 Energy and MatterWhat are the different forms of energy related to changes in matter?Like matter, energy is never created or destroyedIt simply is transformed changes from one form to anotherEnergy is all around you and comes in many formsForms of energy related to changes in matter include, kinetic, potential, chemical, electromagnetic, electrical, and thermal energyWhat is kinetic energy?What are some examples?All matter has energy of at least one formKinetic energy is the energy of matter in motionFor example, a rolling bowling ball has kinetic energy and can do work by knocking down bowling pinsIf you drop the bowling ball on your toe, youll experience the work done by the kinetic energy of the falling ballEven though you cant see them, the smallest particles of matter have kinetic energy because they are in constant random motion

What is potential energy?Potential energy is the energy an object has because of its positionFor example, when you stretch a rubber band, your action gives potential energy to the rubber band to snap back and do workWhat are some other examples of potential energy?The action of pushing your bike to the top of a hill takes energyThis energy is not wasted instead it is stored in you and in the bikeThis stored energy (potential energy) will change to kinetic energy as you coast back down the hillAs you went up the hill you increased the potential energy of both you and the bike

What is chemical energy?The internal energy stored in the chemical bonds between atoms is a form of potential energy called chemical energy When a chemical change occurs, these bonds are broken and new bonds are formedIf the change is exothermic ( energy is released), some of the chemical energy is transformed and released most often as thermal energy

What is electromagnetic energy?Electromagnetic energy is a form of energy that travels through space as wavesVisible light or the energy that reaches Earth in the form of sunlight is one example of electromagnetic energyOther types of electromagnetic energy are radio waves, infrared rays from heat lamps, the waves that heat food in a microwave oven, ultraviolet rays, and x-rays

ActivotesHow are chemical and physical changes related to electromagnetic energy?Chemical changes can give off electromagnetic energy, such as the light from a wood fireAlso, electromagnetic energy may cause both chemical and physical changes in matter to occurFor example, a microwave oven can change a frozen block of food into a hot meal, which is a physical change

What is electrical energy?Electrical energy is the energy of electrically charged particles (electrons) moving from one place to anotherElectrons move from one atom to another in many chemical changesElectrolysis is an example of a chemical change that involves electrical energyWhat happens during electrolysis?In electrolysis, electrical energy can be used to break down water (H20) into its elements (H2 and O2)Two metal strips (electrodes) are placed in a solutionEach electrode is attached to a wire that is connected to a source of electrical energy (battery)

What happens during electrolysis?When the energy begins to flow atoms of one kind of element lose electrons at one electrode At the other electrode atoms of the other element gain electronsIn the case of water, bubbles of oxygen gas and hydrogen gas form at separate electrodes so that the elements are separated How is energy transformed?During a chemical change, chemical energy may be changed to others forms of energy and other forms of energy may also be changed to chemical energyFor example, the burning of fuel is a chemical change that transforms chemical energy and releases it as thermal energy and electromagnetic energyWhen you push a bike up a hill, chemical energy from foods you ate is transformed into the kinetic energy of your moving musclesIn a similar way, other forms of energy can be changed into chemical energy

Why is photosynthesis one of the most important energy transformation?During photosynthesis, plants transform electromagnetic energy from the sun into chemical energy as they make molecules of sugarThese plants, along with animals and other living things that eat plants, transform this chemical energy once againIt becomes the energy needed to carry out life activities

What kind of energy do you see here?