Question

what mass (in grams) of aspirin (c9h8o4) is produced from 72.0 g of c7h6o3 assuming 95.0% yield from the reaction below? c7h6o3(s) + c4h6o3(l) → c9h8o4(s) + hc2h3o2(aq)

Explanation:

Step1: Calculate moles of \(C_7H_6O_3\)

Molar mass of \(C_7H_6O_3=(7\times12)+(6\times1)+(3\times16)=138\space g/mol\)
Moles of \(C_7H_6O_3=\frac{72.0\space g}{138\space g/mol}\approx0.5217\space mol\)

Step2: Determine moles of \(C_9H_8O_4\) (theoretical)

From the balanced equation \(C_7H_6O_3(s)+C_4H_6O_3(l)\to C_9H_8O_4(s)+HC_2H_3O_2(aq)\), mole ratio \(C_7H_6O_3:C_9H_8O_4 = 1:1\)
Theoretical moles of \(C_9H_8O_4 = 0.5217\space mol\)

Step3: Calculate theoretical mass of \(C_9H_8O_4\)

Molar mass of \(C_9H_8O_4=(9\times12)+(8\times1)+(4\times16)=180\space g/mol\)
Theoretical mass \(=0.5217\space mol\times180\space g/mol = 93.906\space g\)

Step4: Calculate actual mass (considering yield)

Yield \( = 95.0\%=0.95\)
Actual mass \(=93.906\space g\times0.95\approx89.2\space g\)

Answer:

\(89.2\space g\)