Question

Consider the lattice energy of any ionic compound. What combination of ions and charges will produce the largest (in magnitude) lattice energies? c small ions and small charges c large ions and large charges c small ions and large charges r large ions and small charges

Answer 1

Concepts and reason

Lattice energy is the amount of energy required to completely dissociate one mole of an ionic crystal lattice into its constituent ions or the amount energy released when one mole ions in their gaseous state to combine to form a crystal lattice.

Fundamentals

Lattice energy can be calculated using the following formula:

${\rm{Lattice}}{\kern 1pt} {\kern 1pt} {\kern 1pt} {\rm{energy}}{\kern 1pt} {\kern 1pt} {\kern 1pt} {\kern 1pt} {\rm{ = }}{\kern 1pt} {\kern 1pt} {\kern 1pt} \frac{{{\rm{k}}{\kern 1pt} {{\rm{Q}}_1}{{\rm{Q}}_2}}}{{\rm{r}}}$

Here, k is a constant, ${{\rm{Q}}_1}$ and ${{\rm{Q}}_2}$ are the charges of ions and r is the distance between the ions.

As the size of the ions increases, distance between the ions (r) increases.

Hence, small ions produce largest lattice energy

The following combination of ions and charges will produce largest lattice energy.

oSmall ions and large charges.

Ans:

The following combination of ions and charges will produce largest lattice energy.

oSmall ions and large charges.