Question

We now examine some examples that illustrate how to relate the mass of a gravimetric precipitate to the quantity of the original analyte. The general approach is to relate the moles of product to the moles of reactant.

Short answer

When piperzine combines with acetic acid, the mass percentage of product is 86.71%.

Step-by-step solution

Concept used

By dividing the determined mass of the substance by the total mass of the sample whole multiplied by , the mass percentage of the compound may be derived.

The formula may be used to compute the mass percent, and the formula can also be used to provide a solution.

$$\begin{gathered} \mathbf{Molarity}\mathbf{}\left(M\right)\mathbf{=}\frac{\mathbf{Moles}\mathbf{}\mathbf{of}\mathbf{}\mathbf{solute}\left(\mathrm{inmol}\right)}{\mathbf{Volume}\mathbf{}\mathbf{of}\mathbf{}\mathbf{solution}\left(\mathrm{inL}\right)} \\ \mathit{M}\mathit{o}\mathit{l}\mathit{a}\mathit{r}\mathit{m}\mathit{a}\mathit{s}\mathit{s}\mathbf{=}\frac{\mathbf{Mass}}{\mathbf{Mole}} \end{gathered}$$

How to relate the mass of a gravimetric precipitate to the quantity of the original analyte

When piperzine interacts with acetic acid, the mass percentage of product is calculated.

Consider that 0.800 g of piperizine diacetate 0.3854 g sample.

The following is the reaction between piperzine and acetic acid:

The moles of piperizine diacetate are computed as follows:

$\frac{0.800\mathrm{g}}{206.240\mathrm{g}/\mathrm{mol}}=3.88\times {10}^{-3}\mathrm{mol}$

Piperizine diacetate is made from one mole of piperizine.

$$\begin{gathered} \mathrm{Molarmass}=\frac{\mathrm{Mnss}}{\mathrm{Mole}} \\ \mathrm{Mass}=86.136\mathrm{g}/\mathrm{mol}\times 3.88\times {10}^{-3}\mathrm{mol} \\ =0.334\mathrm{g} \end{gathered}$$

Piperizine's mass percentage is calculated as Mass percent (in percentage)

$$\begin{gathered} =\frac{\mathrm{Calculated}\mathrm{mass}\left(\mathrm{ingrams}\right)}{\mathrm{totalmass}\left(\mathrm{in}\mathrm{grams}\right)}\times 100 \\ =\frac{0.334\mathrm{g}}{0.3854\mathrm{g}}\times 100 \\ =86.71\% \end{gathered}$$

Thus, the mass percentage of product is 86.71%.