POE EXOTHERMIC

*What will happen when I place these pellets of sodium hydroxide in water?

PREDICTIONS...

place the pellets of NaOH into the water

OBSERVATIONS...

*What does exo mean? to exit or to leave

*What does thermo mean? heat

NOTE

Exothermic Reactions

Heat is a form of energy. In an exothermic reaction energy is released. An exothermic reaction can be detected easily, as heat is given off. Exothermic reactions can be written with energy as one of their products.

EXPLANATION OF POE...

NaOH(s) + H2O(l)_ NaOH(aq)

*What side does the energy go on?

NaOH(s) + H2O(l)_ NaOH(aq) + ENERGY

POE ENDOTHERMIC

*What will happen if I add solid ammonium chloride to water?

PREDICTIONS...

add ammonium chloride to water

OBSERVATIONS...

*What does endo mean? inside

*Knowing that endo means inside and that an exothermic reaction gives off heat...what happens in an endothermic reaction?

NOTE

Endothermic Reactions

In an endothermic reaction energy is absorbed. Energy is written as one of the reactants because it is used up in the reaction.

EXPLANATION OF POE...

NH4Cl(s) +H2O(l)_ NH4Cl(aq)

*Where does the energy go?

NH4Cl(s) +H2O(l) + ENERGY_ NH4Cl(aq)

NOTE

An endothermic reaction can be detected because heat will be absorbed and it will become cold to the touch.

Homework: Heath Chemistry page 117 part E question 20 a-b and 22 a-e