10 g of a sample of a mixture of CaCl 2 and NaCl is treated to precipitate all the calcium as CaCO 3. This CaCO 3 is heated to convert all the Ca to CaO and the final mass of CaO is 1.62 g. The precent by mass of CaCl 2 in the original mixture is

Question

10 g of a sample of a mixture of CaCl 2 and NaCl is treated to precipitate all the calcium as CaCO 3. This CaCO 3 is heated to convert all the Ca to CaO and the final mass of CaO is 1.62 g. The precent by mass of CaCl 2 in the original mixture is (A) 32.1 % (B) 16.2 % (C) 21.8 % (D) 11.0 %

Tardigrade Admin · Accepted Answer

CaCl 2+ NaCl =10 g Let weight of CaCl 2=x g <img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/chemistry/1255caaf1c18f37f7254746ba2eba045-.png" /> Mol of CaO =(1.62/56) ∴ (x/111)=(1.62/56) x=3.21 g % of CaCl 2=(3.21/10) × 100=32.1 %

Q. $10 g$ of a sample of a mixture of $C a C l_{2}$ and $N a Cl$ is treated to precipitate all the calcium as $C a C O_{3}$ . This $C a C O_{3}$ is heated to convert all the $C a$ to $C a O$ and the final mass of $C a O$ is $1.62 g$ . The precent by mass of $C a C l_{2}$ in the original mixture is

$32.1%$

$16.2%$

$21.8%$

$11.0%$

$C a C l_{2} + N a Cl = 10 g$
Let weight of $C a C l_{2} = xg$

$M o l$ of $C a O = \frac{1.62}{56}$
$∴ \frac{x}{111} = \frac{1.62}{56}$
$x = 3.21 g$
$%$ of $C a C l_{2} = \frac{3.21}{10} \times 100 = 32.1%$

Q. 10g of a sample of a mixture of CaCl2​ and NaCl is treated to precipitate all the calcium as CaCO3​. This CaCO3​ is heated to convert all the Ca to CaO and the final mass of CaO is 1.62g. The precent by mass of CaCl2​ in the original mixture is

32.1%

16.2%

21.8%

11.0%