Use the Born-Haber Cycle to determine the lattice energy of chromium (Il) oxide given the information below. For full credit, write out the chemical equation for each step.
Construct a Born-Haber cycle for the formation of the
hypothetical compound NaCl2 where the sodium ion has a 2+ charge
(the 1st and 2nd ionization energies for sodium are 496 KJ/mol and
4562 KJ/mol respectively).
(a) How large would the lattice energy need to be for the
formation of NaCl2 to be exothermic
(b) If we were to estimate the lattice energy of NaCl2 to be
roughly equal to that of MgCl2 (2326 KJ/mol), what value would you
obtain for...
Born-Fajans-Haber Cycle
Suppose a chemist discovers a new metallic element and names it
"Xhaustium" (Xh).
Xh exhibits chemical behaviour similar to an alkaline
earth.
Xh(s) + F2(g) → XhF2(s)
Lattice energy for XhF2
-2120. kJ/mol
First Ionization energy of Xh
390. kJ/mol
Second Ionization energy of Xh
702 kJ/mol
Electron affinity of F
-327.8 kJ/mol
Bond energy of F2
154 kJ/mol
Enthalpy of sublimation (atomization) of
Xh
200. kJ/mol
Use the above data to calculate ΔH°f for
Xhaustium fluoride.
As we know the enthalpy of solution is equal to the addition of
lattice energy and hydration energy.
Why does solubility depend on the relative magnitude of the
lattice energy compared to the hydration energy?
Use the Born-Haber cycles to determine the solvation energy for
these two compounds: NaCl MgCl2. Solvation energy is
deltaH for the process.
ions gas phase --> ions aqueous solution.
(Make the ions in aq solution the starting & ending point
for the cylce.)
MgCl2 pulls water from your skin in a painful manner
where NaCl(s) in your hand has no effecfts.
Calculate the relevant enthalpychange for MgCl2 and
NaCl that can be used to explain the statement above.
Use the Born-Haber cycles to determine the solvation energy for
these two compounds: NaCl MgCl2. Solvation energy is
deltaH for the process.
ions gas phase --> ions aqueous solution.
(Make the ions in aq solution the starting & ending point
for the cylce.)
MgCl2 pulls water from your skin in a painful manner
where NaCl(s) in your hand has no effecfts.
Calculate the relevant enthalpychange for MgCl2 and
NaCl that can be used to explain the statement above.