Q26Long answer
Calcium chloride when dissolved in water dissociates into its ions according to the following equation. CaCl2 (aq) → Ca2+ (aq) + 2Cl– (aq) Calculate the number of ions obtained from CaCl2 when 222 g of it is dissolved in water.
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1 mole of calcium chloride = 111g ∴ 222g of CaCl2 is equivalent to 2 moles of CaCl2 Since 1 formula unit CaCl2 gives 3 ions, therefore, 1 mol of CaCl2 will give 3 moles of ions 2 moles of CaCl2 would give 3×2=6 moles of ions. No. of ions = No. of moles of ions × Avogadro number = 6 × 6.022 ×10 23 = 36.132 ×10 23 = 3.6 132 ×1024 ions