0.81 moles
Explanation:
cobalt chloride when dissolved in water dissociate into cobalt and chloride ions as shown;
CoCl₂ (s) → [Co²⁺](aq) + 2[Cl⁻] (aq)
The mole ratio between CoCl₂ and [Co²⁺] is 1 ; 1 while the mole ratio between CoCl₂ and [Cl⁻] is 1 : 2
Therefore; 0.27 moles of CoCl₂ will form;
(1 * 0.27) = 0.27 moles of [Co²⁺] ions
(2 * 0.27) = 0.54 moles of [Cl⁻] ions
Total moles of dissociated ions are;
0.27 + 0.54
= 0.81 moles
5.20 mol C6H12* (84.2 g/mol C6H12)= 4.38*10^(2) g C6H12.
The answer should only have three significant figures, according to the numbers in the problem.
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