Thermochemistry 5.1 Measuring Energy Changes

Where is potential energy stored

In the chemical bonds of the reactants/products

Where is kinetic energy found

In the temperature of the reacting mixture where atoms and ions are present

Why is energy always transferred from a warmer body to a cooler one

Entropy

What happens when heat is transferred

There is an increase in average kinetic energy in the particles

What is an endothermic process example

The bond dissociation energy is the energy required to break a bond

What is an exothermic process example

Bond making

What is the goal when making bonds? what does it mean for the energy?

The goal is more stability and it means less potential energy.

Limitation when it comes to enthalpy

Any change in value not accounted for in the result of the initial + final measurements.

What is enthalpy

The amount of energy stored in a bond between atoms in a molecule.

What determines an intensive and extensive property? Which type is heat and temperature?

1. Temp is intensive because it doesn’t depend on the amount

2. Heat is extensive because heat is a measure of the total energy of a substance

Compare the product’s stability to the reactants in an exothermic and endothermic reaction.

1. In endothermic the product is more stable compared to reactants because of the lower potential energy

2. In exothermic the product is less stable compared to the reactants because of the higher potential energy