91影视

The mass of the element or solute divided by the mass of the compound or solute equals the mass percent.

The percent mass is computed as follows,

$$\begin{gathered} \mathbf{\%}{\mathbf{massCI}}^{\mathbf{鈥�}}\mathbf{=}\mathbf{18980}\frac{\mathbf{mg}}{\mathbf{kg}}\mathbf{脳}\frac{\mathbf{1}\mathbf{kg}}{\mathbf{1}\mathbf{.}\mathbf{0}\mathbf{脳}{\mathbf{10}}^{\mathbf{6}}\mathbf{mg}}\mathbf{脳}\mathbf{100}\mathbf{\%} \\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{1}\mathbf{.}\mathbf{898}\mathbf{\%}\mathbf{CI}\mathbf{鈥�} \\ \mathbf{}\mathbf{\%}{\mathbf{massNa}}^{\mathbf{+}}\mathbf{=}\mathbf{10560}\frac{\mathbf{mg}}{\mathbf{kg}}\mathbf{脳}\frac{\mathbf{1}\mathbf{kg}}{\mathbf{1}\mathbf{.}\mathbf{0}\mathbf{脳}{\mathbf{10}}^{\mathbf{6}}\mathbf{mg}}\mathbf{脳}\mathbf{100}\mathbf{\%} \\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{1}\mathbf{.}\mathbf{0560}\mathbf{\%}{\mathbf{Na}}^{\mathbf{+}} \\ \mathbf{\%}{\mathbf{massSO}}_{\mathbf{4}\mathbf{}}^{\mathbf{2}\mathbf{鈥�}}\mathbf{=}\mathbf{2650}\frac{\mathbf{mg}}{\mathbf{kg}}\mathbf{脳}\frac{\mathbf{1}\mathbf{kg}}{\mathbf{1}\mathbf{.}\mathbf{0}\mathbf{脳}{\mathbf{10}}^{\mathbf{6}}\mathbf{mg}}\mathbf{脳}\mathbf{100}\mathbf{\%} \\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{265}\mathbf{\%}{\mathbf{SO}}_{\mathbf{4}\mathbf{}}^{\mathbf{2}\mathbf{鈥�}} \\ \mathbf{\%}{\mathbf{massMg}}^{\mathbf{2}\mathbf{+}}\mathbf{=}\mathbf{1270}\frac{\mathbf{mg}}{\mathbf{kg}}\mathbf{脳}\frac{\mathbf{1}\mathbf{kg}}{\mathbf{1}\mathbf{.}\mathbf{0}\mathbf{脳}{\mathbf{10}}^{\mathbf{6}}\mathbf{mg}}\mathbf{脳}\mathbf{100}\mathbf{\%} \\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{127}\mathbf{\%}{\mathbf{Mg}}^{\mathbf{2}\mathbf{+}} \\ \mathbf{}\mathbf{\%}{\mathbf{massCa}}^{\mathbf{2}\mathbf{+}}\mathbf{=}\mathbf{400}\frac{\mathbf{mg}}{\mathbf{kg}}\mathbf{脳}\frac{\mathbf{1}\mathbf{kg}}{\mathbf{1}\mathbf{.}\mathbf{0}\mathbf{脳}{\mathbf{10}}^{\mathbf{6}}\mathbf{mg}}\mathbf{脳}\mathbf{100}\mathbf{\%} \\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{0400}\mathbf{\%}{\mathbf{Ca}}^{\mathbf{2}\mathbf{+}} \\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{\%}{\mathbf{massK}}^{\mathbf{+}}\mathbf{=}\mathbf{380}\frac{\mathbf{mg}}{\mathbf{kg}}\mathbf{脳}\frac{\mathbf{1}\mathbf{kg}}{\mathbf{1}\mathbf{.}\mathbf{0}\mathbf{脳}{\mathbf{10}}^{\mathbf{6}}\mathbf{mg}}\mathbf{脳}\mathbf{100}\mathbf{\%} \\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{0380}\mathbf{\%}{\mathbf{K}}^{\mathbf{+}} \\ \mathbf{}\mathbf{\%}{\mathbf{massHCO}}_{\mathbf{3}}\mathbf{=}\mathbf{140}\frac{\mathbf{mg}}{\mathbf{kg}}\mathbf{脳}\frac{\mathbf{1}\mathbf{kg}}{\mathbf{1}\mathbf{.}\mathbf{0}\mathbf{脳}{\mathbf{10}}^{\mathbf{6}}\mathbf{mg}}\mathbf{脳}\mathbf{100}\mathbf{\%} \\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{0}\mathbf{.}\mathbf{0140}\mathbf{\%}{\mathbf{HCO}}_{\mathbf{3}} \end{gathered}$$

So, the different percentage has been calculated.

To calculate mass percent of Na⁺ion, compute the total mass of ions in seawater

Here, the total mass of ions

$$\begin{gathered} \mathbf{=}\mathbf{18980}\mathbf{+}\mathbf{10560}\mathbf{+}\mathbf{2650}\mathbf{+}\mathbf{1270}\mathbf{+}\mathbf{400}\mathbf{+}\mathbf{380}\mathbf{+}\mathbf{140} \\ \mathbf{=}\mathbf{34380}\mathbf{mg}\mathbf{/}\mathbf{kg} \end{gathered}$$

The mass percent of sodium ions is then calculated,

$$\begin{gathered} \mathbf{\%}{\mathbf{massNa}}^{\mathbf{+}}\mathbf{=}\frac{\mathbf{10560}}{\mathbf{34380}}\mathbf{脳}\mathbf{100}\mathbf{\%} \\ \mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{}\mathbf{=}\mathbf{30}\mathbf{.}\mathbf{72}\mathbf{\%} \end{gathered}$$

i)Alkaline earth metal ions are Mg²⁺ and Ca²⁺ ions.

Add the ${\mathbf{Mg}}^{\mathbf{2}\mathbf{+}}$and ${\mathbf{Ca}}^{\mathbf{2}\mathbf{+}}$percentages together.

$$\begin{gathered} \mathbf{0}\mathbf{.}\mathbf{127}\mathbf{\%}\mathbf{+}\mathbf{0}\mathbf{.}\mathbf{0400}\mathbf{\%} \\ \mathbf{=}\mathbf{0}\mathbf{.}\mathbf{167}\mathbf{\%} \end{gathered}$$

ii) Alkali metal ions areNa⁺and K⁺ ions.

Add the${\mathbf{Na}}^{\mathbf{+}}$and${\mathbf{K}}^{\mathbf{+}}$percentages together.

localid="1657086437804" $$\begin{gathered} \mathbf{1}\mathbf{.}\mathbf{056}\mathbf{\%}\mathbf{+}\mathbf{0}\mathbf{.}\mathbf{0380}\mathbf{\%} \\ \mathbf{=}\mathbf{1}\mathbf{.}\mathbf{094}\mathbf{\%} \end{gathered}$$

In seawater, there are more alkali metal ions than alkaline earth metal ions.

i) Cations percentage

Let鈥檚 determine the total percentage of cations,

$$\begin{gathered} \mathbf{0}\mathbf{.}\mathbf{167}\mathbf{\%}\mathbf{+}\mathbf{1}\mathbf{.}\mathbf{094}\mathbf{\%} \\ \mathbf{=}\mathbf{1}\mathbf{.}\mathbf{261}\mathbf{\%} \end{gathered}$$

ii) Anions percentage

Let鈥檚 determine the total percentage of anions,

$$\begin{gathered} \mathbf{1}\mathbf{.}\mathbf{898}\mathbf{\%}\mathbf{+}\mathbf{0}\mathbf{.}\mathbf{265}\mathbf{\%}\mathbf{+}\mathbf{0}\mathbf{.}\mathbf{0140}\mathbf{\%} \\ \mathbf{=}\mathbf{2}\mathbf{.}\mathbf{177}\mathbf{\%} \end{gathered}$$

In seawater, there are more anions than cations.