Oceans Flashcards
most ionic substances only dissolve in….
polar solvents
most covalent substances only dissolve in….
non-polar solvents
ionic solids dissolve in…
to make….
water
aqueous solutions
standard lattice enthalpy is….
the enthalpy change when 1 mol of an ionic lattice is formed from its gaseous ions under standard conditions
lattice enthalpy is always….
because….
negative
bonds are being broken and energy is being released
the more negative the lattice enthalpy….
the stronger the bonding
enthalpy change of hydration ions is…
the enthalpy change when 1 mol of aqueous ions is formed from gaseous ions
the enthalpy change of solution is….
the enthalpy change when 1 mol of an ionic substance dissolves enough to form an indefinitely dilute solution
you can use a _______ _____ or _____ _____ _____ to find the enthalpy change of solution
enthalpy cycle
enthalpy level diagram
charge density of an ion =
charge / radius
ions with higher charge density have more exothermic lattice enthalpy, why?
the ions are better at attracting each other so ionic bonds are stronger. meaning more energy is released when bonds are made
ions with higher charge density have more exothermic hydration enthalpy, why?
ions are better at attracting water molecules so the intermolecular bonds are stronger. meaning more energy is released when bonds are made
entropy, S, is…
a measure of the number of ways that particles can be arranged and the number of ways the energy can be shared out between particles
how does physical state affect entropy?
solids - hardly any disorder
liquids - some disorder
gases - most disordered
which physical state has the highest entropy?
gas
which physical state has the lowest entropy?
solid
how does no. of moles affect entropy?
when no. of moles increases, entropy increases
ΔtotS =
ΔsysS + ΔsurrS
ΔsysS =
S products - S reactants
ΔsurrS =
-enthalpy change / T (k)
a feasible reaction is….
one that once started will carry on to completion without zero energy being supplied to it
for a reaction to be feasible the total entropy change must be…
positive or zero
the equation for finding the temperature for a feasible reaction to occur is…
T = ΔH / ΔsysS
Ksp is….
the solubility product