Introduction to Thermochemistry and Energy Concepts

Thermochemistry

The study of heat changes that occur during chemical reactions and physical changes of state.

Energy

The ability to do work or supply heat.

Kinetic Energy

Energy associated with the motion of an object.

Potential Energy

Stored energy based on an object's position or arrangement.

Heat

(q) a form of energy that flows from warmer objects to cooler objects.

Temperature

A measure of heat; increase heat, increase temperature.

Chemical Potential Energy

Stored energy in chemical bonds that depends on the type of atoms and arrangement.

Exothermic Reaction

A chemical reaction where potential energy is converted to heat, resulting in heat being given off.

Endothermic Reaction

A chemical reaction where heat is absorbed and converted to potential energy, resulting in a cool feeling.

Law of Conservation of Energy

Energy can neither be created nor destroyed, only converted from one form to another.

Joule (J)

A unit of energy.

calorie (cal)

A unit of energy; specifically, a chemistry calorie.

Calorie (Cal)

A unit of energy; specifically, a food calorie.

Conversion Factor

1 food Cal = 1000 chemistry cal.

Energy Conversion

1 cal = 4.18 J.

Energy Conversion Example

How many calories are in 287J? 287 J = 68.7 cal.

Energy Conversion Example

How many kJ are equal to 1478cal? 1478 cal = 6.178 kJ.

Equilibrium

The point at which two objects in contact reach the same temperature.

Forms of Energy

Kinetic, Potential, Heat, Solar, Nuclear, Wind, Sound, Magnetic.