Which general trends in first ionization energy and electronegativity values are demonstrated by group 15 elements as they are considered in order from top to bottom(1) the first ionization energy decreases and the electronegativity decreases.
(2) the first ionization energy increases and the electronegativity increases.
(3) the first ionization energy decreases and the electronegativity increases.
(4) the first ionization energy increases and the electronegativity decreases.

(1) The first ionization energy decreases and the electronegativity decreases

Explanation:

When we move from top to bottom in a periodic table the atomic size of elements increases and it becomes easy to remove valence electron from the elements at low energy.Thus decrease in ionisation energy from top to bottom.

Metallic character increases as we move down into a group of a periodic table and metals have low electronegativity than non-metals. So, value of electronegativity decreases from top to bottom.

the energy to form plasma comes from heat or electricity in the atmosphere!

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