Alkanes

Let us analyze both statements given in the question:

1. Statement I: The chlorides of Be (beryllium) and Al (aluminum) have Cl-bridged structures. Both are soluble in organic solvents and act as Lewis bases.
   Analysis:
   • The chlorides of Be and Al (BeCl₂ and AlCl₃) do indeed form Cl-bridged structures. BeCl₂ forms polymeric chains, while AlCl₃ forms a dimer.
   • However, these chlorides are known to act as Lewis acids, not Lewis bases. They can accept electron pairs, which is a characteristic of Lewis acids.
   • Both BeCl₂ and AlCl₃ are soluble in organic solvents, which is consistent, but the statement about acting as Lewis bases renders the statement incorrect.
2. Statement II: Hydroxides of Be and Al dissolve in excess alkali to give beryllate and aluminate ions.
   Analysis:
   • Beryllium hydroxide, Be(OH)₂, and aluminum hydroxide, Al(OH)₃, are amphoteric. This means they can react with both acids and bases.
   • In excess alkali, Be(OH)₂ dissolves to form the beryllate ion [Be(OH)₄]^2-, and Al(OH)₃ dissolves to form the aluminate ion [Al(OH)₄]^-.
   • This characteristic makes Statement II true as it accurately describes the behavior of these hydroxides.

Conclusion: Based on the analysis, Statement I is false because BeCl₂ and AlCl₃ act as Lewis acids, not bases. Statement II is true because both hydroxides dissolve in excess alkali to form the corresponding ionic species. Thus, the correct answer is: Statement I is false but Statement II is true.