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Day 5:. Check and go over sig fig worksheet Pg 1 in Chapter 2 packet Energy Notes **Element Quiz FRIDAY!!**. Energy Notes:. Energy Heat transfer and Heat Law of Conservation of Energy Heat and Temperature Exothermic/Endothermic. What is Energy?. Energy: the capacity to do work
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Day 5: • Check and go over sig fig worksheet • Pg 1 in Chapter 2 packet • Energy Notes • **Element Quiz FRIDAY!!**
Energy Notes: • Energy • Heat transfer and Heat • Law of Conservation of Energy • Heat and Temperature • Exothermic/Endothermic
What is Energy? • Energy: the capacity to do work • Examples: • Forming a new compound • Moving something • Generating light Energy TRANSFER is always involved when there is a change in matter • Whether it’s a chemical or physical change Energy is never created or destroyed in a change of matter – just transferred
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 physical or chemical change, the total quantity of energy remains constant. • Even though it may seem that energy is being destroyed or created, energy is actually being transferred.
Kinetic vs. potential • Kinetic Energy • Energy of motion • In Chemistry: how fast or slow molecules are moving • Potential Energy • Stored energy or energy of position • In Chemistry: how far apart the molecules are
Conservation of energy in a chemical reaction Surroundings Surroundings System Energy System After reaction Before reaction Notice that the energy of the reactants and products increases, while the energy of the surrounding decreases. However the total energy does not change.
Energy gets transferred by… • Light • Chemicals • Motion (mechanical) • Electrical • Sound • Heat
How do we Measure Energy? • Units to measure Energy: • Calorie (cal): • the energy required to raise the temperature of 1 gram of water by 1ºC • Joules (J): • The SI Unit for energy
Heat • Heat is energy transferred between two objects with different temperatures Heat is always transferred in a very specific way: High Energy to Low Energy.
Temperature • The measurement of kinetic energy of a substance • (How fast or slow the particles that make it up are moving)
Day 6: • Finish notes/demos • Lab!! • Practice Worksheet • **Element quiz tomorrow! - Friday!!**
Demos!! • Demos - demos - DEMOS!! • Take note of observations.
Exothermic Processes • Releasing of energy into the surrounding materials is called an exothermic process. **A chemical reaction that feels warm to the touch • Evidence: • Surrounding materials get hotter from the energy released by the reaction • Examples: • Freezing Water
Endothermic Processes • Absorption of energy from the surrounding materials is called an endothermic process. **A chemical reaction that feels cold to the touch • Evidence: • Surrounding materials get colder due to the energy being removed by the reaction. Examples: • Ice melting
Lab! • Exothermic & endothermic processes • CW/HW: pgs. 1 – 3