Final answer:
The pyridinium ion (C5H5NH+) has a total of eight valence electrons, calculated by summing the valence electrons of nitrogen and hydrogen atoms and then subtracting one electron for the positive charge of the ion.
Step-by-step explanation:
The pyridinium ion, which is the conjugate acid of the weak base pyridine, contains a total of eight valence electrons. This is calculated by considering the valence electrons of each atom in the molecule and the charge of the ion. A nitrogen (N) atom typically has five valence electrons, and each hydrogen (H) atom contributes one valence electron. Since pyridinium has four hydrogen atoms, this gives us four valence electrons from hydrogen. To determine the total number of valence electrons in the pyridinium ion (C5H5NH+), we sum the electrons from nitrogen and hydrogen and then subtract one electron due to the positive charge of the ion. Thus, the calculation is 5 (from N) + 4 (from 4 H atoms) - 1 (due to the 1+ charge), resulting in eight valence electrons.