Exam 26: S-Block Chemistry

The Kapustinskii equation predicts that the lattice enthalpy increases from MCl to MCl₂ to MCl₃.

Match the reaction products with their reactants. -sodium + oxygen

Sodium hydroxide is prepared industrially by electrolysis of a solution of sodium chloride.

Magnesium hydroxide is widely used in the indigestion remedy, milk of magnesia. Barium hydroxide would be a better antacid than magnesium hydroxide.

Many metals form metallocene complexes where a metal ion is sandwiched between two aromatic rings. The ion is considered to be equally coordinated to all carbons in the ring. For example cyclopentadience (C₅H₆) reacts with sodium to form the ionic compound (C₅H₅)^- Na⁺. The ring structure of the ligand is aromatic and the structure drawn as delocalised. This ionic salt is then used to produce a host of coordination complexes e.g with Fe, Mg, Be etc which consist of a divalent cation and two cycolpentadienyl rings. Most of these ions form a sandwich complex where the metal ion lies equidistantly between the two rings. However, in the gas phase, beryllium coordinates to one ring or the other but not both. By considering the properties of beryllium, suggest why this might be.

The lattice enthalpy as determined by the Kapustinskii equation of K₂O is larger in magnitude than the lattice enthalpy of K₂O₂.

The compound EtMgBr is used extensively in organic chemistry as a _______ reagent.

Match the reaction products with their reactants. -sodium + ammonia

Methyl lithium exists as a

Beryllium hydroxide, like aluminium hydroxide, shows ____________ behaviour.

Compounds of beryllium form _____ solutions.

The properties of the Group 1 metals include? Please select all that apply.

In the suboxide Cs₁₁O₃ , the electrons are delocalized over the whole structure. Give a formula that more adequately represents this arrangement.

The properties of beryllium are markedly different from the rest of the Group 2 elements. Why? Please select all that apply.

Beryllium normally has a coordination number of _ in its compounds.

Beryllium chemistry is very different to the rest of the group. Which of the following statements apply to beryllium and not the rest of Group 2. Please select all that apply.

While Group 1 metal cations generally coordinate weakly to most ligands, they do form stable complexes with size selective macrocyclic ligands.

Match the reaction products with their reactants. -heat + sodium peroxide

Neither the Born Lande or the Kapustinskii equations correctly calculate the lattice energy for beryllium compounds. Why?

The Down's cell is used to produce sodium metal by electrolysis of molten sodium chloride.