Choose the correct statements from the following.

a.  Beryllium is not readily attacked by acids because of the presence of an oxide film on the surface of the metal

b.  Beryllium sulphate is readily soluble in water as the greater hydration enthalpy of Be2+ overcomes the lattice enthalpy factor

c.  Beryllium exhibits coordination number more than four

d.  Beryllium oxide is purely acidic in nature

Choose the correct option
1. (a, b)
2. (b, c)
3. (c, d)
4. (a, d)

Due to diagonal relationship, beryllium is similar to aluminium. It also forms an oxide film which is very stable on the surface of the metal. 
Beryllium sulphate is soluble in water due to high hydration energy. Beryllium does not exhibit coordination number more than four. Like Al2O3, BeO is amphoteric in nature.