The whole topic, fill in a few diagrams, and you have everything you need to know on 2 pages..**

HideShow resource information
  • Created by: Aisha
  • Created on: 05-08-09 16:01
Preview of Energetics

First 216 words of the document:

This is the region which is being investigated. (The reactants and the products.)
This is everything that is affected by the chemical reaction. (The rest of the universe.)
A reaction that gives out heat to the surroundings is EXOTHERMIC
A reaction that takes in heat from the surroundings is ENDOTHERMIC
Enthalpy Change (H)
This is the heat energy change measured under conditions of constant heat and pressure.
If trying to work out the H from a graph H = H2 ­ H1
Thermochemical Equation
This is a stoichiometric equation which includes the states of the reactants and products,
and a value for the enthalpy change of the forward reaction.
Exothermic Reactions Endothermic Reactions
This is a method of measuring the enthalpy change of a reaction by considering
temperature changes in the immediate surroundings of the chemical reaction.
A Calorimeter
This is an insulated vessel which is used for measuring the amount of energy released/
absorbed during a chemical/ physical change.
Amount of heat transferred = Mass of the substance × Specific Heat Capacity × Temperature Change
q = mcT
Enthalpy Change = ± (Endothermic/Exothermic) Amount of heat transferred ÷ Amount of substance
H = ± q / n

Other pages in this set

Page 2

Preview of page 2

Here's a taster:

Calculate the heat capacity of the Calorimeter
c = nH / T
q = cT
Hess's Law
The overall enthalpy change is independent upon the route taken.
Enthalpy of Formation
The enthalpy change when one mole of a compound is formed under its constituent
elements under standard conditions, all reactants and products in their standard
states.…read more

Page 3

Preview of page 3

Here's a taster:

Increase the quantities used so values are easier to read for more accurate results.
Increase the accuracy of measuring the volume of water by using a burette.
Repetition of experiments.…read more


No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all resources »