What are the main factors due to which the ionisation enthalpy of the main group elements tends to decrease down a group ?

The main factors which affect corrosion are

Does the ionisation enthalpy decreases along a group ? Give reasion

What are the 'two main groups of living things? :

What is the family names of elements be-longing to the 17 th group?

What is the common valency of elements be-longing to the 17 th group?

Transition metals are widely used as catalysts in industrial processes. Why do the transition elements exhibit greater similarity in properties compared to main group elements along the period as well as down the group?

Which group of elements belong to transition elements?

Ionization enthalpy is an important periodic property. a) What is the unit in which it is expressed? b) What are the factors influencing ionization enthalpy? c) How ionisation enthalpy varies in the periodic table?