Question

Place the following in order of increasing radius and explain why you put it in that order.
Ca²⁺, S^2-, Cl^-

Place the following in order of increasing IE1 and explain why you put it in that order.
N, F, As

Place the following in order of decreasing magnitude of lattice energy and explain why you put it in that order.
Li₂O, Rb2S, K₂O

Answer 1

Ca^2+ , S^2- , Cl^- are isoelectronic series.

more negative charge anion is more radius. cation radius is less than anion.

S^2- > Cl^- > Ca^2+

N, As contains half filled electron configuration. so it stable. so it has more ionisation potential . But N is less radius than As

N>As>F

lattice energy is inversly proportional to sum radius of cation and anion.

The radius is increases Li^+ > K^+ > Rb^+

less radius cation has more lattice energy.

Li2O>K2O>Rb2S