Calorimetry

Calorimeter

A calorimeter is a device used to measure the heat flow of a chemical reaction or physical change.

Bomb Calorimeter

A device for determining heats of combustion by igniting a sample in a high pressure of oxygen in a sealed vessel and measuring the resulting rise in temperature.

Endothermic

A physical process or chemical reaction characterized by or causing the gain of heat to the system from the surroundings.

Exothermic

A physical process or chemical reaction characterized by or causing the liberation or release of heat from the system to the surroundings.

Calorimetry

Calorimetry is the science of measuring the heat flow into or out of a system for chemical or physical changes It is a method to measure the heat effect of a process,which could be physical changes, such as melting, evaporation, dehydration (could also be defined as chemical change), or it can be a chemical change, such as acid-base neutralization, dissolving, solid-state reaction, and crystal phase transition

Energy

Energy may be defined as the ability to do work. It is a scalar physical quantity. Although energy is conserved, there are many different types of energy, such as kinetic energy, potential energy, light, sound, and nuclear energy.

Enthalpy

Enthalpy is the amount of heat content used or released in a system at constant pressure. Enthalpy is usually expressed as the change in enthalpy. (ΔH) FOR GASES: The change in enthalpy (ΔH) is related to a change in internal energy (ΔE ) and a change in the volume (ΔV ), which is multiplied by the constant pressure of the system. ΔE = q−PΔV ΔH=ΔE+Δ(PV)

The Energy Transfer Equation

Q=mc ΔT The quantity of energy = the mass times the specific heat times the change in temperature.

Heat Capacity

The amount of energy (heat) required to raise the temperature of a given amount of a substance by 1ºC

Calorie

The amount of energy (heat) required to raise the temperature of one gram of water from 14.5°C to 15.5°C. 1 calorie = 4.184 joules. The specific heat of water is 4.184 J / (g x °C)

Heat of solution

The amount of heat absorbed in the formation of solution that contains one mole of solute; the value is positive if heat is absorbed (endothermic) and negative if heat is released (exothermic).

Heat of Fusion

The amount of heat required to melt one gram of solid at its melting point with no change in temperature. Usually expressed in J/g.

Heat of Vaporization

The amount of heat required to vaporize one gram of a liquid at its boiling point with no change in temperature. Usually expressed in J/g.

Heat of Neutralization

The change in enthalpy that occurs when one equivalent of an acid and one equivalent of a base undergo a neutralization reaction to form water and a salt. It is a special case of the enthalpy of reaction. It is defined as the energy released with the formation of 1 mole of water.

Heat of combustion

The energy released as heat when a compound undergoes complete combustion with oxygen under standard conditions. The chemical reaction is typically a hydrocarbon reacting with oxygen to form carbon dioxide, water and heat.

Specific Heat

The energy required to raise one gram of any substance by 1 degree Celsius. Units = J / (g x °C)

Change in Enthalphy (ΔH)

The gain or loss of energy to or from a system as a result of chemical or physical change.

Work

Work is given in joules [J]* when the force is in Newtons [N] and the distance is in meters [m]. One joule is the amount of work required to displace an object one meter against a force of one Newton. *The SI units for energy is the joule (J).