Identify the correct statement from the following

Options

A. Lithium and magnesium show some similarities in their physical properties as they are diagonally placed in periodic table.
B. Lithium is softer among all alkali metals.
C. Lithium chloride is deliquescent and crystallises as a hydrate `LiCl.H_(2)O`
D. The order of hydration enthalpies of alkaline earth cations
`Be^(2+)ltMg^(2+)ltCa^(2+)ltSr^(2+)ltBa^(2+)`

Answer

A

Explanation

a. Lithium shows diagonal relationship with magnesium hence, their physical and chemical properties are almost similar.
b. Lithium is much harder than other alkali metals.
c. Licl is deliquescent and crystallises from aqueous solution as hydrate `LiCl.2H_(2)O`
d. The hydration enthalpies of alkaline earth metal ions decreases with increase in ionic size down the group.
So. Order of hydration enthalpy is
`Be^(2+)gtMg^(2+)gtCa^(2+)gtSr^(2+)gtBa^(2+)`