☰
The s-Block Elements
Draw the structure of: (i) BeCl2 (vapour) (ii) BeCl2 (solid).
In the solid state, BeCl2 has polymeric chain structure. Be atom is tetrahedrally surrounded by four Cl atoms - two are bonded by covalent bonds while the other two by coordinate bonds. The polymeric structure of BeCl2 is due to its electron deficient nature. It has only four electrons in valence shell and can accept two pairs of electrons from neighbouring chlorine atoms to complete their octet.
In the vapour state, beryllium chloride exists as a dimer (Be2Cl4) which dissociates at 1200 K into monomer (BeCl2) which has a linear shape.
Sponsor Area
In aqueous solution, Li+ ion has lowest mobility. Why?
Lithium has highest ionisation energy in group 1 elements, yet it is strongest reducing agent. Comment.
The softness of group 1 elements increases down the group with increasing atomic number. Give reason.
Which is the most reactive alkali metal and why?
Why alkali metals do not form M2+ ions?
Name the radio active element in group 1. How does it resemble with the remaining elements of the group?
Why alkali metals are normally kept in kerosene oil?
Why lithium cannot be stored in kerosene?
Why does lithium form complexes?
Why are alkali metal ions diamagnetic and colourless?
Sponsor Area
Sponsor Area