<span>a large amount of energy is released when water dissociates into oppositely charged ions.</span>
An element or compound which occurs naturally in the earth is a mineral. Minerals are substances formed naturally in the Earth.They have a definite chemical composition and structure. For example, the minerals gold or diamonds you’d find by mining or panning for gold since they are found naturally in the Earth.
<span>Answer: 100 ml
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<span>Explanation:
1) Convert 1.38 g of Fe₂S₃ into number of moles, n
</span>i) Formula: n = mass in grass / molar mass
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ii) molar mass of </span><span>Fe₂S₃ =2 x 55.8 g/mol + 3 x 32.1 g/mol = 207.9 g/mol
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iii) n = 1.38 g / 207.9 g/mol = 0.00664 moles of <span>Fe₂S₃
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<span>2) Use the percent yield to calculate the theoretical amount:
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<span>65% = 0.65 = actual yield/ theoretical yield =>
</span>theoretical yield = actual yield / 0.65 = 0.00664 moles / 0.65 = 0.010 mol <span>Fe₂S₃</span><span>
3) Chemical equation:
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<span> 3 Na₂S(aq) + 2 FeCl₃(aq) → Fe₂S₃(s) + 6 NaCl(aq)
4) Stoichiometrical mole ratios:
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<span>3 mol Na₂S : 2 mol FeCl₃ : 1 mol Fe₂S₃ : 6 mol NaCl
5) Proportionality:
</span>2moles FeCl₃ / 1 mol Fe₂S₃ = x / 0.010 mol Fe₂S₃
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=> x = 0.020 mol FeCl₃
6) convert 0.020 mol to volume
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<span>i) Molarity formula: M = n / V
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<span>ii) V = n / M = 0.020 mol / 0.2 M = 0.1 liter = 100 ml
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