The order of first ionization enthalpy (\( I_{E_1} \)) for these elements is:
\(\text{Al} < \text{Si} < \text{C} < \text{N}\)
Thus, nitrogen (\( \text{N} \)) has the highest first ionization enthalpy among the given options.
The Correct Answer is: N
Total number of nucleophiles from the following is: \(\text{NH}_3, PhSH, (H_3C_2S)_2, H_2C = CH_2, OH−, H_3O+, (CH_3)_2CO, NCH_3\)