text stringlengths 1 1.32M |
|---|
Practice theoretical examples |
1 Using an energy level diagram calculate the Hs of ammonium chloride crystals given that |
Hf of NH3 aq 8054kJ mole1 |
Hf of HCl aq 16446kJ mole1 |
Hf of NH4Cl aq 2617483kJ mole1 |
Hs of NH4Cl aq 168517kJ mole1 |
N2g 1 H2g Cl2 Hf2617483kJ NH4Cls aq |
xHs |
aq aq |
8054kJH1 16446kJH2 |
NH3 aq HClaq 168517kJH3 NH4Cls |
H1 H2 H3 H4 Hf |
8054kJ 16446kJ 168517kJ 2617483kJ Hf |
Hf 336kJmole1 |
Study the energy cycle diagram below and use it to |
aIdentify the energy changes H1 H2 H3 H4 H5 H6 |
H1 enthalpyheat of formation of sodium chloride Hf |
H2 enthalpyheat of atomization of sodium Hat |
H3 enthalpyheat of ionizationionization energy of sodium H i |
H4 enthalpyheat of atomization of chlorine Hat |
H5 enthalpyheat of electron affinity of chlorine He |
H6 enthalpyheat of latticeLattice energy of sodium chlorideH l |
b Calculate H1 given that H2 108kJ H3500kJ H4 121kJ H5 364kJ and H6 766kJ |
Working |
H1 H2 H3 H4 H5 H6 |
Substituting |
H1 108kJ 500kJ 121kJ 364kJ 766kJ |
H1 401kJmole1 |
c Given the that |
i Ionization energy of sodium 500kJmole1 |
iiHat of sodium 110kJmole1 |
iii Electron affinity of chlorine 363kJmole1 |
ivHat of chlorine 120kJmole1 |
v Hf of sodium chloride 411kJ calculate the lattice energy of sodium chloride using an energy cycle diagram |
Working |
Applying Hess law then |
Hf Ha Hi Ha He Hl |
Substituting |
411 108kJ 500kJ 121kJ 364kJ x |
411 108kJ 500kJ 121kJ 364kJ x |
x 776kJmole1 |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.