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Chemistry

Hi! Does anyone know where this question is from

This question is about sodium and its compounds.
The Born-Haber cycle for sodium oxide is shown in GRAPH A (not to scale).

Sodium peroxide is used in diving apparatus to produce oxygen from carbon dioxide.

2Na2O2(s) + 2CO2(g) --> 2Na2CO3(s) + O2(g)

a) Plot the relative values of the first four ionization energies of sodium.

b) Explain why the alkali metals (group 1) have similar chemical properties.

c) Describe the structure and bonding in solid sodium oxide.

di) Calculate the values of the following changes using section 8 of the data booklet.

ΔHatomization (Na) = +107 kJ mol-1

ΔHatomization (O) = +249 kJ mol-1

½O2(g) --> O2-(g):

Na(s) --> Na+(s):

dii) The standard enthalpy of formation of sodium oxide is -414 kJ mol-1. Determine the lattice enthalpy of sodium oxide, in kJ mol-1, using section 8 of your data booklet and your answers to (di).

diii) Justify why K2O has a lower lattice enthalpy (absolute value) than Na2O.

e) Write equations for the separate reactions of solid sodium oxide and solid phosphorus(V) oxide with excess water and differentiate between the solutions formed.

f) Sodium peroxide, Na2O2, is formed by the reaction of sodium oxide with oxygen.

2Na2O(s) + O2(g) --> 2Na2O2(s)

Calculate the percentage yield of sodium peroxide if 5.00 g of sodium oxide produces 5.50 g of sodium peroxide.

gi) Determine the enthalpy change, ΔH, in kJ, for this reaction using data from the TABLE A and section 12 of the data booklet.

gii) Outline why bond enthalpy values are not valid in calculations as that in (gi).

h) An allotrope of molecular oxygen is ozone. Compare, giving a reason, the bond enthalpies of O to O bonds in O2 to O3.

i) The reaction of sodium peroxide with excess water produces hydrogen peroxide and one other sodium compound. Suggest the formula of this compound.
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