consider the balanced equation. pcl3 + 3h2o → h3po3 + 3hcl what is the percent yield of hcl if 42.0 g of hcl…

Explanation:

Step1: Calculate molar mass of $PCl_3$

The molar mass of $P$ is $30.97\ g/mol$ and of $Cl$ is $35.45\ g/mol$. So molar mass of $PCl_3=30.97 + 3\times35.45=30.97+ 106.35 = 137.32\ g/mol$.

Step2: Determine moles of $PCl_3$

Moles of $PCl_3=\frac{mass}{molar\ mass}=\frac{62.0\ g}{137.32\ g/mol}\approx0.4529\ mol$.

Step3: Use stoichiometry to find moles of $HCl$ produced theoretically

From the balanced equation $PCl_3 + 3H_2O\rightarrow H_3PO_3+3HCl$, the mole - ratio of $PCl_3$ to $HCl$ is $1:3$. So moles of $HCl$ produced theoretically $= 3\times0.4529\ mol = 1.3587\ mol$.

Step4: Calculate molar mass of $HCl$

The molar mass of $H$ is $1.01\ g/mol$ and of $Cl$ is $35.45\ g/mol$. So molar mass of $HCl = 1.01+35.45 = 36.46\ g/mol$.

Step5: Calculate theoretical yield of $HCl$

Theoretical yield of $HCl=moles\times molar\ mass=1.3587\ mol\times36.46\ g/mol\approx49.54\ g$.

Step6: Calculate percent - yield of $HCl$

Percent yield of $HCl=\frac{Actual\ yield}{Theoretical\ yield}\times100=\frac{42.0\ g}{49.54\ g}\times100\approx85.0%$.

Answer:

85.0%