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Question
Calcium chloride when dissolved in water dissociates into its ions according to the following equation.
\[\ce{CaCl2} (aq) → {Ca^{2+} (aq) + 2{Cl}- (aq)}\]
Calculate the number of ions obtained from CaCl2 when 222 g of it is dissolved in water.
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Solution
\[\ce{CaCl2} → Ca^{2+} + 2Cl^-\]
111 g (1 moles) → 1 moles + 2 moles
222 g (2 moles) → 2 moles + 4 moles
Total number of ions given by 2 moles of CaCl2 = 6
Number of ions = Number of moles of ions × NA
= 6 × 6.022 × 1023
= 3.6132 × 1024 ions
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