Lead oxide can be decomposed by heating. What is the percent yield of the decomposition reaction if 22.3 grams of PbO are heated to give 18.0 g of Pb

Respuesta :

The correct answer would be 82%.

Answer: The percent yield of the reaction is 86.96 %

Explanation:

To calculate the number of moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}[/tex]     .....(1)

Given mass of PbO = 22.3 g

Molar mass of PbO = 223 g/mol

Putting values in equation 1, we get:

[tex]\text{Moles of PbO}=\frac{22.3g}{223g/mol}=0.1mol[/tex]

The chemical equation for the decomposition of PbO follows:

[tex]2PbO\rightarrow 2Pb+O_2[/tex]

By Stoichiometry of the reaction:

2 moles of produces 2 moles of Pb

So, 0.1 moles of PbO will produce = [tex]\frac{2}{2}\times 0.1=0.1mol[/tex] of Pb

Now, calculating the mass of Pb from equation 1, we get:

Molar mass of lead = 207 g/mol

Moles of lead = 0.1 moles

Putting values in equation 1, we get:

[tex]0.1mol=\frac{\text{Mass of lead}}{207g/mol}\\\\\text{Mass of lead}=(0.1mol\times 207g/mol)=20.7g[/tex]

To calculate the percentage yield of the reaction, we use the equation:

[tex]\%\text{ yield}=\frac{\text{Experimental yield}}{\text{Theoretical yield}}\times 100[/tex]

Experimental yield of Pb = 18.0 g

Theoretical yield of Pb = 20.7 g

Putting values in above equation, we get:

[tex]\%\text{ yield of Pb}=\frac{18.0g}{20.7g}\times 100\\\\\% \text{yield of Pb}=86.96\%[/tex]

Hence, the percent yield of the reaction is 86.96 %.