Brainiest to the one who answer this

1.- describe the trend in ionization energy as the atomic number increases across a period.

2.- describe the trend in ionization energy as the atomic number increases down a group.

1. Across a period , the ionization energy increases  because the formation of a cation becomes more difficult owing to the increase in nuclear charge.

2. Ionization energy decreases down the group because the outer electrons become progressively separated from the nucleus and so are less tightly held .

Explanation:

answer; economic order quantity;

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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