Lithium Nitride Formation and Properties

This screencast explains how to construct a Born-Haber cycle for lithium nitride (Li3N) to estimate its enthalpy change of formation. The process involves atomization and ionization steps, electron gain enthalpies, and the use of the Kapustinskii equation to estimate lattice energy. The final calculation confirms that the formation of lithium nitride is exothermic, with an enthalpy change of -165 kJ/mol.

What is the primary purpose of constructing a Born-Haber cycle for lithium nitride?

• To estimate the enthalpy change of formation

• To determine the melting point of lithium nitride

• To find the boiling point of lithium nitride

• To calculate the density of lithium nitride

Which of the following is NOT a step in the Born-Haber cycle for lithium nitride?

• Lattice energy calculation

• Electron gain enthalpy for nitrogen

• Ionization of nitrogen

• Atomization of lithium

How many lithium atoms are considered in the formula unit for lithium nitride?

• Two

• One

• Three

• Four

What is the Kapustinskii equation used for in the context of lithium nitride?

• To determine the molecular weight

• To find the melting point

• To estimate lattice energy

• To calculate the boiling point

In the Kapustinskii equation, what does the constant K represent?

• 17,900 Pomers KJ per mole

• The number of ions in the formula unit

• The cationic radius

• The anionic radius

What is the cationic charge (Z Plus) for lithium in the Kapustinskii equation?

• Zero

• Two

• Three

• One

What is the calculated lattice energy for lithium nitride using the Kapustinskii equation?

• 7,800 KJ per mole

• 4,000 KJ per mole

• 5,240 KJ per mole

• 6,500 KJ per mole

What is the final enthalpy change of formation for lithium nitride?

• -100 K per mole

• -165 K per mole

• -200 K per mole

• -250 K per mole

What does a negative enthalpy change of formation indicate about the reaction?

• The reaction is endothermic

• The reaction is exothermic

• The reaction is at equilibrium

• The reaction is non-spontaneous

Which of the following is true about the formation of lithium nitride from its elements?

• It is a reversible process

• It requires a catalyst

• It is an exothermic process

• It is an endothermic process