average bond enthalpy
enthalpy change of breaking 1 mol of bonds in a gasous molecules
what is standard enthalpy chnage of combustion
enthalpy chnage when 1 mol of a substance completly combusts
- always exothermic
what is the standard enthalpy of formation
enthaply chnage when 1 mol of compoud is formed from its elements
- can be exothermic or endothermic
what is the enthalpy of neuatralsdiation
the enthalpgy change when 1 mol of H20 is formed from the reaction of H+ and OH-
- always exothermic
what is the equation for enthaply change
H = mcT / n
what is method 1 of calorimentry
combusiton calorimetry where mass of substance is burned , heats a know mass of water and then emasure the temperature change of the water
in combsution caloimentry what acts as the surranding and the chemical system
surrounding - water
chemical system - the fuel burning
what is an example of exothemric reaction
combsution , respiration
what is an example of a endothemric reaction
thermal decomposation
sources of error in calorimentry is
heat loss to surraandings
incomplete combusion of fuel
how do we mnimises heat loss to surrandings
add lid to beaker
how do we mnimise incomplete combsution
ensure plentiful suppply of oxygen
what is method 2 of calorimentry
calorimentry with a reaction in a soltuion
what acts as the surradning and the chemical system in method 2 of colroiemntry
solution acts as the surradings , chemical system is the chemical reactang
does bond breaking require energy
yes . endothermic
does bond making require energy
no it releases energy . exothermic
what is the statment for exothermic
energy required to break the bond is less than the energy released to make the bonds
what is the statement for ednothermic
energy required to break the bond is more than the energy released to make the bonds
bond enthalpy eqation
bonds broken - bonds formed
reactant - product
what does hess law state
enthaplgy change for a chemical reaction is indepedant of the route taken
how to find combustion
Reactant - product
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bonding and structure 2.2.239
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alkens 4.1.324
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group 2 3.1.216
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halogens 3.1.325
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reaction rates 3.2.222
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enthaply changes 3.2.122
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perodicity 3.1.117
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organic synthesis 4.2.313
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chemical equilbrium18
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aromatic compounds7
-
organic23
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bonding and structure 2.2.28
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acids13
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acids6
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acids and bases4
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amount of substance9
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amines 6.2.110
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lattice enthalpy 5.2.16
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amino acids ,amided and chiraity 6.2.27
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organic synthesis 6.2.537
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6.2.3 polyesters and polyamides7
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transition metals20
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chromatagrpahy 6.3.17
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redox and electron potetial9
