1) The trend has a positive correlation 2) Across a period, shielding has no effect, because the number of energy levels remains constant. The nuclear charge of the elements depends on the valence electrons. It is lower on the left side of the periodic table, where the nucleus wants to lose electrons. Also, the atom is smaller on the left than on the right of the period.
Work Step by Step
1) As electronegativity increases, so does the first ionization energy 2) Look at Page 174