© All Rights reserved @ LearnWithDash
Step-by-Step Solution
Step 1: Identify the Chemical Reaction
Aniline ( C_6H_5NH_2 ) undergoes acetylation to form acetanilide ( C_6H_5NHCOCH_3 ). We assume complete reaction of the given amount of aniline.
Step 2: Calculate the Number of Moles of Aniline
The molar mass of aniline is 93\,\text{g mol}^{-1} . If 1.86\,\text{g} of aniline is taken:
\text{Moles of aniline}
=
\frac{\text{Given mass}}{\text{Molar mass}}
=
\frac{1.86}{93}
=
0.02\,\text{mol}
Step 3: Determine the Theoretical Yield of Acetanilide
The molar mass of acetanilide is 135\,\text{g mol}^{-1} . Since 1 mole of aniline produces 1 mole of acetanilide:
\text{Theoretical yield of acetanilide}
=
\text{(moles of aniline)} \times \text{(molar mass of acetanilide)}
=
0.02 \times 135
=
2.7\,\text{g}
Step 4: Adjust for Product Loss During Purification
10% of the product is lost during purification. This means only 90% is recovered:
\text{Actual yield of acetanilide}
=
\text{(theoretical yield)} \times 90\%
=
2.7 \times 0.90
=
2.43\,\text{g}
Step 5: Express the Final Amount as Requested
The question asks for the amount of acetanilide in grams as “_____ \\times 10 - 2”. Since 2.43\,\text{g} = 243 \\times 10^{-2}\,\text{g} , the required numerical value is 243.
Final Answer
Amount of acetanilide obtained after purification = 243 \\times 10^{-2}\\,\text{g} .
