Which of the following properties increase down a column in the periodic table? effective nuclear charge ionic radii ionization energy number of valence shell electrons

 The  properties that increase  down a column  in the periodic  table  is

Ionic radii

Explanation

In periodic table column is also referred  to as group.

Ionic radii  tend to increase  as you move  from top to bottom of the group.  This is because down the group there is increase of extra shell  which increases the distance  from the nucleus to outer shell.

The  ionization energy  and effective nuclear charge  decreases down the  group while  number  of valence shell electrons remain the same.

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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