Question

If the yield of chloroform obtainable from acetone and bleaching powder is 58%. The weight of acetone required for producing 47.8 g of chloroform is :
\[2C{{H}_{3}}COC{{H}_{3}}+6CaOC{{l}_{2}}\to Ca{{(C{{H}_{3}}COO)}_{2}}+2CHC{{l}_{3}}+3CaC{{l}_{2}}+2Ca{{(OH)}_{2}}\]
A. 40
B. 20
C. 4
D. 10

Answer 1

Hint:. We can calculate the moles by using the following formula
Number of moles = $\dfrac{W}{MW}$
Here W = weight of the chemical
MW = molecular weight of the chemical

Complete step by step answer:
- In the question it is given that two moles of acetone produces two moles of chloroform and we can see the same thing from the following reaction.
\[2C{{H}_{3}}COC{{H}_{3}}+6CaOC{{l}_{2}}\to Ca{{(C{{H}_{3}}COO)}_{2}}+2CHC{{l}_{3}}+3CaC{{l}_{2}}+2Ca{{(OH)}_{2}}\]
- Means one mole of acetone will give one mole of chloroform as the product.

- Number of moles of chloroform given in the question is as follows.
Number of moles = $\dfrac{W}{MW}$
Here W = weight of the chloroform = 47.8
MW = molecular weight of the chloroform = 119.5
- Therefore the number of moles of chloroform is

 Number of moles of chloroform $=\dfrac{W}{MW}=\dfrac{47.8}{119.5}=0.4$
- Then 0.4 moles of chloroform is produced from 0.4 moles of acetone.
- Weight of the acetone $ = 0.4\times 58=23.2g$
- In the question it is given that the yield is 58%.

- Therefore weight of the acetone required for producing 47.8 g of chloroform is
\[\begin{align}
  & =\dfrac{23.2}{58} \\
 & =40g \\
\end{align}\]
- So, The weight of acetone required for producing 47.8 g of chloroform is 40 g.
So, the correct answer is “Option A”.

Note: Generally acetone is used to produce chloroform in a few industries. Two moles of acetone react with bleaching powder and forms one mole of calcium acetate and two moles of chloroform, three moles of calcium chloride, and two moles of calcium hydroxide as the products.