thermodynamics

Question 1

define enthaply of lattice dissociation

Answer 1

the standard enthaply change when one mole of solid ionic compound dissociates into its gaseous ions

Question 2

define enthaply of lattice formation

Answer 2

the standard enthalpy change when one mole of solid ionic compumd is formed from its gaseous ions

Question 3

define enthalpy of atomization

Answer 3

the standard enthalpy change when one mole of gaseous atoms are formed from an element in its standard state

Question 4

define mean bond enthaloy

Answer 4

the enthalpy change when one mole of gaseous molecules each break a covalent bonds to form 2 free radicals averaged over a range of compounds

Question 5

define first electron affinity

Answer 5

the standard enthalpy change when one mole of gaseous atoms is converted into a mole of gaseous ions each with a single negative charge under standard conditions

Question 6

define first ionization enthalpy

Answer 6

the standard enthalpy change when one mole of electrons is removed from one mole of gaseous atoms to give one mole of gaseous ions each with a single positive charge

Question 7

define enthalpy of hydration

Answer 7

the standard enthalpy change when one mole of gaseous ions is converted into one mole of aqueous ions

Question 8

define enthalpy of solution

Answer 8

the standard enthalpy change when one mole of solute dissolves to form its aqueous ions

Question 9

sterength of ionic lattice effect on lattice enthaply

Answer 9

stronger ionic lattices have a more exothermic lattice formation enethaply
stronger ionic lattices have a more endothermic lattice dissociation enthaply

Question 10

theoretical model for mearsuring ionic bond strenght

Answer 10

perect ionic model
assumption made about ions: perfect spheres/point charges
bonding: purely ionic

Question 11

experimental model for mearsuring ionic bond strenght

Answer 11

born haber cycle
Assumption made about ions: polarisble ions
Bonding: ionic plus some covalent character

Question 12

define entropy and units

Answer 12

a mearsure of the amount of disorder in a system
JK-1mol-1

Question 13

change in state effect on entropy

Answer 13

solid-> liquid->gas means increases in entropy
gas->liguid->solid means decrease in entropy

Question 14

number of moles effect on entropy

Answer 14

small number of moles -> large number of moles means increases in entropy
large -> small numner of moles means decreases in entrhopy

Question 15

calcuting entropy changs

Answer 15

sum to entropy of product - sum of entropy of reactants

Question 16

eqautionf of change in gibbs free enrgy

Answer 16

¬G=¬H -T¬S

Question 17

when is reaction feasible

Answer 17

¬G is less than or eqaul to zero

Question 18

gibbs eqaution in form to plot

Answer 18

¬G= -¬ST +¬H