Answer:
1.50 moles Cl⁻
Step-by-step explanation:
To find the amount of chloride ions, you need to (1) convert grams to moles (using the molar mass) and then (2) convert moles AlCl₃ to moles Cl⁻. It is important to arrange the conversions/ratios in a way that allows for the cancellation of units. The final answer should have 3 sig figs like the given value.
Molar Mass (AlCl₃): 26.982 g/mol + 3(35.453 g/mol)
Molar Mass (AlCl₃): 133.341 g/mol
1 mole AlCl₃ = 1 mole Al³⁺ and 3 moles Cl⁻
66.7 g AlCl₃ 1 mole 3 moles Cl⁻
-------------------- x ------------------ x --------------------- = 1.50 moles Cl⁻
133.341 g 1 mole AlCl₃