150 mL of 0.25 mol/L magnesium chloride solution and 150 mL of 0.35 mol/L silver nitrate solution are mixed together. After reaction is completed; calculate the concentration of nitrate ions in solution. Assume that the total volume of the solution is 3.0 x 10^2 mL

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Explanation:

Magnesium chloride and silver nitrate reacts at a ratio:

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In reality, the nitrate ion from silver nitrate did not take part in this reaction at all. Consider the ionic equation for this very reaction:

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The precipitate silver chloride is insoluble in water and barely ionizes. Hence, isn't rewritten as ions.

Net ionic equation:

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Calculate the initial quantity of nitrate ions in the mixture.

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Since nitrate ions do not take part in any reaction in this mixture, the quantity of this ion would stay the same.

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However, the volume of the new solution is twice that of the original nitrate solution. Hence, the concentration of nitrate ions in the new solution would be of the concentration in the original solution.

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