You need to make an aqueous solution of 0.181 M calcium acetate for an experiment in lab, using a 250 mL volumetric flask. How much solid calcium acetate should you add? In grams. 

1 Answer

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jerichorayel | College Teacher | (Level 2) Senior Educator

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To solve this problem we can apply the formula in getting the molarity of the solution. We know that:

`Molarity = (mol es)/(Liters of Solution)`

and moles of any compound can be represented as:

`Mol es = (given mass)/(molar mass)`


Now the problem is asking for the given mass or the mass needed to create 0.181 M calcium acetate.

First, we have to get the moles of calcium acetate using the formula of the molarity:

`Molarity = (mol es)/(Liters of Solution)` 

`Mol es = Molarity * Liters of solution`

`Mol es = (0.181) * (0.25)`

Moles = 0.04525 moles of calcium acetate


Then we can get the given mass:

`Mol es = (given mass)/(molar mass)`

`Given mass = Mol es of calcium ace tate * Molar mass`

`Given mass = (0.04525)*(158.17)`

Given mass = 7.16 grams calcium acetate - final answer