Although there are many ions in seawater, the overall charges of the dissolved cations and anions must maintain charge neutrality. Consider only the six most abundant ions in seawater, as listed in Table $18.5\left(\mathrm{Cl}^{-}, \mathrm{Na}^{+},\right.\( \)\mathrm{SO}_{4}^{2-}, \mathrm{Mg}^{2+}, \mathrm{Ca}^{2+},\( and \)\left.\mathrm{K}^{+}\right),$ calculate the total charge in Coulombs of the cations in \(1.0 \mathrm{~L}\) of seawater. Calculate the total charge in Coulombs of the anions in \(1.0 \mathrm{~L}\) of seawater. To how many significant figures are the two numbers equal?

In summary, to calculate the total charge of cations and anions in 1.0 L of seawater, you need to follow these steps: 1. Determine the concentrations of the ions listed in Table 18.5 (Cl-, Na+, SO4(2-), Mg2+, Ca2+, and K+). 2. Calculate the moles of each ion in 1 L of seawater by multiplying their concentrations (in moles/L) by the volume of seawater (1 L). 3. Calculate the total charge of cations and anions by multiplying the number of moles of each ion by their respective charges (in elementary charge units, e) and the elementary charge (1.602×10^{-19} C). Sum up the charges separately for cations and anions. 4. Compare the total charges of cations and anions to ensure they are equal and maintain charge neutrality in seawater. Determine the number of significant figures they share in common.