$29.$ A $50\mathrm{.}0$ mL solution of $50\mathrm{.}0$ mM Na$3$PO$4$ is combined with a $50\mathrm{.}0$ mL solution

of $90\mathrm{.}0$ mM NiCl$2.$ What will the concentration of Ni$2+$ ions in the solution be

once the limiting reagent is consumed completely?

A$.0\mathrm{.}00$ mM

B$.7\mathrm{.}50$ mM

C$.20\mathrm{.}0$ mM

D$.37\mathrm{.}5$ mM

E$.45\mathrm{.}0$ mM

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