The calculated electron gain enthaly values for alkaline earth metals and noble gases are positive . How can you explain this ?

How does the electron gain enthalpy values vary in a group and a period ?

Why Noble gases have zero electron gain enthalpy?

How beryllium differs from the other alkaline earth metals .

How does alkaline earth metals react with (a) water and (b) air .

Knowing the electron gain enthalpy values for O to O^(-) and O to O^(2-) as -141 and "702 kJ mol"^(-1) respectively, how can you account for the formation of a large number of oxides having O^(2-) species and not O^(-) ?

Which metals are more reactive and which are less reactive ? How can you say ?

In alkaline earth metals, the electrons are more firmly held to the nucleus and hence

For a element, the value of electron gain enthalpy is positive. Which type of element it may be ? What this value is positive ?

(A): Electron gain enthalpy of noble gases is very less (R): Atoms of noble gases have completely filled orbitals