physical chemistry Flashcards
energy change of a reaction
EC associated with a stated reaction. Quantities of substances in standard states react completely under standard conditions
EC of formation
EC when 1 mole of a substance is produced from its elements in their standards states under standard conditions
EC of combustion
EC when 1 mole of a substance is burned completely in oxygen under standard conditions
EC of neutralisation
EC when solutions of acid and alkali react together under standard conditions to produce water
what does calorimetry measure
temperature change over time
for bonds to be broken energy is…
taken in from surroundings
for bonds to be made energy has to be…
given out
when energy is taken in from the surrounding enthalpy change is…
positive / endothermic
when energy is being released from surroundings EC is…
negative / exothermic
enthalpy change calc
H = E needed to break bonds + E released to make bonds
activation energy is the…
minimum amount of energy needed for a reaction to take place
specific heat capacity is the E needed to …
raise 1g of substance by 1K without a change in state
ways to decrease heat loss in calorimetry
bomb calorimeter
polystyrene cup
lid
bond E data is the E required to…
break one mole of stated bond in a gaseous state under standard conditions
mean bond enthalpy tell you how much..
E is needed to break a bond
