Developing Fuels Flashcards
explain why stereoisomerism can occur in but-2-ene (2 marks)
there is a lack of rotation around the C=C bond
and the groups on each end of the carbon atom are different
number of moles in gas =
vol in dm3 / 24.0
or
vol in cm3 / 24000
what is the ideal gas equation?
pV = nRT
what is R in the gas equation?
gas constant - 8.314
enthalpy change is..
the heat energy transferred in a reaction at a constant pressure
what are the enthalpy change units?
kj mol-1
in an exothermic reaction energy is…
given out to surroundings
in endothermic reactions energy is…
absorbed
in an exothermic reaction delta H is..
negative
in an endothermic reaction delta H is..
positive
bond breaking is an ____ process
endothermic
bond breaking is an _____ reaction
endothermic
enthalpy change of reaction =
total energy absorbed to break bonds - total energy released in making bonds
standard enthalpy change of reaction is…
the enthalpy change when the reaction occurs in molar quantities shown in the chemical equation, under standard conditions
Enthalpy is…..
the energy content stored in a system
standard enthalpy change of combustion is…..
The enthalpy change that takes place when 1 mol of substance reacts completely with oxygen under standard conditions.
standard enthalpy change of formation is….
the enthalpy change that takes place when one mole of a compound is formed from its constituent parts in their standard states under standard conditions
standard enthalpy change of neutralisation is…
the enthalpy change that takes place when 1 mol of hydrogen ions react with 1 mol of hydroxide ions to form water under standard conditions
Hess’ law is when
a reaction can take place by more than one route and the initial and final conditions are the same, the total enthalpy change for each route is the same
for combustion data in hess cycles the arrow points…
downwards
for formation data in hess cycles the arrow points…
up
fractional distillation is…
separation of a liquid mixture into fractions differing in boiling point, by means of distillation.
using a fractionating column