Learning Intentions

• You can describe exothermic and endothermic reactions and be able to identify them through word problems.

• You can describe the difference between a system and its surroundings.

• You can determine if a reaction is endothermic or exothermic from observations of the reaction.

• You can draw an energy diagram for a reaction based on observations.

• You can analyze how the amount of a reactant will affect energy changes.

Content Standards being covered:

HS-PS1-4. Develop a model to illustrate that the release or absorption of energy from a chemical reaction system depends upon the changes in total bond energy.
182. As bonds break, energy is absorbed and as bonds are formed, energy is released
183. In an exothermic reaction, the energy of the products of a reaction will be less than the energy of the reactants. Energy is released and the enthalpy is positive (increases)
184. In an endothermic reaction, the energy of the products is higher than that of the reactants. Energy was absorbed and enthalpy is a negative (decreased)

Habits of Mind/Life skills being covered:

Applying past knowledge to current situations

Journal Entry:

What is actually happening in a chemical reaction at the atomic level? How is energy involved?