L22 - Thermodynamics

How to experimentally measure the heat of a reaction

Exothermic Process

Energy exiting the system; leads to a system with lower energy than its initial state.

Endothermic Process

Energy entering the system; leads to a system with higher energy than its initial state.

Heat

A transfer of thermal energy that results in a change in temperature.

Heat Capacity

Constant dependent on the material relating heat and temperature.

Heat Capacity of a System

The amount of energy required to raise its temperature by one degree Celsius or one Kelvin.

Translational, Rotational, and Vibrational Motion

Types of motion affected by heat flow in liquid water.

Latent Heat of a Phase Transition

Heat that goes into a system at the phase transition; not part of the heat capacity.

Specific Heat Capacity

The amount of joules you have to put in to raise one gram of that material by one degree Celsius.

Molar Heat Capacity

Heat capacities per mole.

Calorimeter

Device or setup used to measure energy flow or heat flow.

Calorimetry

Technique of measuring heat flow.

Closed System

A system at constant volume that can exchange heat with the surroundings (but not matter).

Heat Flow in Reaction

Heat flow is equal in magnitude but opposite in sign to the heat flow into the calorimeter.

Close System Definition

A system can't change volume but can exchange heat with the surroundings, then the heat flow is gonna be equal to all of the energy change is going to be transferred by heat flow.

Enthalpy Change

The heat flow at constant pressure is the total change in energy plus p delta v.