Question

Question 26
Calcium chloride when dissolved in water dissociates into its ions according to the following equation.

$CaC{l}_2\left(aq\right)\to C{a}^{2+}\left(aq\right)+2C{l}^{-}\left(aq\right)$

Calculate the number of ions obtained from $CaC{l}_2$ when 222 g of it is dissolved in water.

Answer 1

1 mole of calcium chloride = 40+(35.5 X 2)= 40+71 =111g
$\therefore$ 222g of $CaC{l}_2$ is equivalent to 2 moles of $CaC{l}_2$.

Calcium chloride when dissolved in water dissociates into its ions as given below,
$CaC{l}_2\left(aq\right)\to C{a}^{2+}\left(aq\right)+2C{l}^{-}\left(aq\right)$
Here, number of moles of ions in 1 mole of $CaC{l}_2$ = 3

No. of ions = No. of moles of ions $\times$ Avogadro number
Number of ions produced by 111g of $CaC{l}_2$ $=3\times 6.022\times {10}^{23}$
Therefore, number of ions produced by 222g of $CaC{l}_2$ $=\frac{3\times 6.022\times {10}^{23}\times 222}{111}$
$=36.132\times {10}^{23}$
$=3.6132\times {10}^{24}$ ions