sblock Elements 2 Question 5
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5. The structures of beryllium chloride in the solid state and vapour phase, respectively are
======= ####5. The structures of beryllium chloride in the solid state and vapour phase, respectively are
3e0f7ab6f6a50373c3f2dbda6ca2533482a77bed (a) dimeric and dimeric
(b) chain and chain
(c) dimeric and chain
(d) chain and dimeric
Show Answer
Answer:
Correct Answer: 5. (b)
Solution:
- The structures of beryllium chloride in the solid state and vapour phase, respectively are dimeric and chain. In vapour phase at above $900^{\circ} \mathrm{C}, \mathrm{BeCl}{2}$ is monomeric having a linear structure $\mathrm{Cl}$ $-\mathrm{Be}-\mathrm{Cl}$. The bonding in $\mathrm{BeCl}{2}$ is covalent and $\mathrm{Be}$ atom accommodates $2+2=4$ electrons in the two $s p$-hybrid orbitals. Below $900^{\circ} \mathrm{C}$, beryllium chloride in vapour phase exists as a mixture of monomer $\mathrm{BeCl}{2}$ and dimer $\mathrm{Be}{2} \mathrm{Cl}_{4}$.
