Question

Use the born-haber cycle to calculate the standard enthalpy of formation for SRI2 (strontium iodide)

Answer 1

To calculate the standard enthalpy of the formation of SRI2 (strontium iodide), use the Born-Haber cycle which breaks down the formation of an ionic solid into a series of steps including the formation of the cation and anion, ionization energy, electron affinity, enthalpy of sublimation, bond dissociation energy, and lattice energy.

Step-by-step explanation:

To calculate the standard enthalpy of the formation of SRI2 (strontium iodide) using the Born-Haber cycle, we need to consider the individual steps involved in the formation of the compound. The Born-Haber cycle breaks down the formation of an ionic solid into a series of steps, including the formation of strontium cation, the formation of iodide anion, the ionization energy of strontium, the electron affinity of iodine, the enthalpy of sublimation of strontium, the bond dissociation energy of iodine, and the lattice energy of strontium iodide.

Answer 2

Born-Haber Process - "Born-Haber process applies Hess's law to calculate the lattice enthalpy(this is a thermodynamic term which equals to the total heat content of a system), by comparing the standard enthalpy change of formation of ionic compound (from the elements) to the enthalpy required to make gaseous ions from the elements".

Step-by-step explanation:

Now the calculations done for SRI2 are as follows:

• Enthalpy of Sublimation of Sr(s)= 164 kJ per mol,
• 1st ionization energy of Sr(g)=549 kJ per mol,
• 2nd ionization energy of Sr(g)=1064 kJ per mol,
• Enthalpy dissociation energy of I2(s)= 62.4 kJ per mol,
• Bond dissociation energy of I2(g)= 152.55 kJ per mol,
• 1st electron affinity of I(g)= -295.15 kJ per mol,
• Lattice energy of SrI2(s)=-1959.75 kJ per mol.

Note - the terms mentioned in the brackets are as, S- solid form, g- Gaseous form.