Bond Enthalpy Calculations Bond energies are used to find the ΔHrꝋ of a reaction when this cannot be done experimentally The process is a step-by-step summation of the bond enthalpies of the all th...
Bonds & Energy When bonds are broken or made enthalpy changes take place A chemical bond is a force of attraction between two atoms Breaking the bond requires the input of energy it is therefor...
Using ∆Hf° to Find Enthalpy Changes Standard Enthalpy of Formation is defined as “The enthalpy change when one mole of a compound is formed from its elements under standard conditions” We can use e...
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Hess's Law using Equations We can use Hess’s Law to solve unknown enthalpy changes by combining equations This requires a methodical step-by-step approach It is necessary to identify how the given ...
Hess's Law using Cycles There are two common methods to solving Hess's Law problems, using cycles and using equations To be successful in using cycles you need to follow carefully a step-by-step pl...
Hess's Law In 1840, the Russian chemist Germain Hess formulated a law which went on to be known as Hess’s Law This went on to form the basis of one of the laws of thermodynamics. The first law of t...
Calorimetry Experiments There are two types of calorimetry experiments you need to know for IB Chemistry: Enthalpy changes of reactions in solution Enthalpy changes of combustion In both cases you ...
Calorimetry Measuring enthalpy changes Calorimetry is a technique used to measure changes in enthalpy of chemical reactions A calorimeter can be made up of a polystyrene drinking cup, a vacuum flas...
