Page 1 - Microsoft Word - Module-3

SUBJECT - CHEMISTRY

S - BLOCK ELEMENTS

SUB TOPIC-GROUP 2 ELEMENTS (ALKALINE EARTH

METALS), TRENDS IN ATOMIC PROPERTIES, PHYSICAL

PROPERTIES, CHEMICAL PROPERTIES AND USES OF

ALKALINE EARTH METALS.

KEY NOTES:

TRENDS IN ATOMIC PROPERTIES:

 Group - 2 elements are Be, Mg, Ca, Sr, Ba, Ra.

2
 General electronic configuration is ns

 Down the group atomic and ionic radii increases

 Ionization enthalpies of alkaline earth metals are

higher than those of the corresponding alkali metals.

Down the group I.E decreases.

 Hydration enthalpies of alkaline earth metal ions

decrease with increase in ionic size.

Be >Mg >Ca >Sr >Ba 2+
2+
2+
2+
2+
 Hydration enthalpies of group 2 metal ions are larger
than group - 1 metal ions.