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Catalyst. What does the Latin root exo- mean? What does the Latin root endo- mean?. End. Justify – TPS. In your opinion, which character would be exothermic? Which character would be endothermic?. Lecture 7.1 – Endothermic and Exothermic Reactions. Today ’ s Learning Targets.
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Catalyst • What does the Latin root exo- mean? • What does the Latin root endo- mean? End
Justify – TPS • In your opinion, which character would be exothermic? Which character would be endothermic?
Today’s Learning Targets • 7.1 – I can describe how the motion of molecules relates to temperature. • 7.2 – I can compare and contrast the ideas of an exothermic reaction and an endothermic reaction.
Today’s Focus Question • Does the breakdown of Flamin’ Hot Cheetos require energy or release energy?
I. Heat and Temperature • Heat is the transfer of energy between substances due to a difference in temperature • Faster a substance moves = higher temperature
II. Exothermic Reactions • Anexothermic reactionis one that releases energy during the reaction • Energy listed as a product in the equation Reactants Products + Energy
III. Endothermic Reactions • An endothermic reactionthat requires energy during the reaction • Energy listed as a reactant in the equation Energy + Reactants Products
Class Example • Is the following reaction endothermic or exothermic? NH4NO3 + 453 kJ/mol HNO3 + NH3
Table Talk • Is the following reaction endo- or exothermic? 2H2 + O2 → 2H2O + 484 kJ/mol
I. Endothermic Phase Changes Absorbs Energy
II. Exothermic Phase Changes Release Energy
Class Example • I have a pot of water and I heat it up until it turns into gas. Is this an endothermic or exothermic process?
Table Talk • You have a test tube where you run the reaction. If the test tube is hot following the reaction, then is this endothermic or exothermic?
White Board Problems 1. The reaction container feels “hot” 2. 500 kJ + 2H2 + O2 → 2H2O 3. Bromine goes from a gas to a liquid 4. Water goes from a solid to a liquid 5. HCl + NaOH H2O + NaCl + 567 kJ 6. 1004 kJ + HNO3 + KOH H2O + KNO3 7. Iodine goes from a liquid to a gas
Work Time Complete the worksheet with your table.
Exit Ticket Identify the following reactions as endothermic or exothermic: 1. Ca(OH)2 + 2HCl CaCl2 + 2H2O + 400 kJ 2. The reaction container “feels cold” 3. Water going from solid to liquid.
Closing Time • Worksheet 7.1 due Thursday/Friday