Stoichiometry

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Name the given compound - Fe₂(CO₃)₃

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Iron (III) carbonate

Front

Determine the oxidation number of each green coloured element in the following ion: S₂O₈^2-

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+7

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Calculate the mass of H₂ gas formed when 40.0 g of Li react with water. Reaction: 2Li(s) + 2H₂O(l) → 2LiOH(aq) + H₂(g). [Ar H =1.0, Li = 6.9, O =16.0]

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5.80 g

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Urea (NH₂)₂CO is prepared by reacting ammonia with carbon dioxide:
2NH₃(g) + CO₂(g) → (NH₂)CO(aq) + H₂O(l)
If 600.0 g of NH₃ are allowed to react with 1142 g of CO₂, determine mass of excess reactant left at the end of the reaction. Options: 456.01 g, 65.09 g, 403.21 g, 363.88 g

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363.88 g

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Calculate the mass of BaSO₄ produced when 1.75 g of MgSO₄ reacts with 2.75 g of BaCl₂. [Mr MgSO₄ = 120.4; BaCl₂ = 208.3; BaSO₄ = 233.4; MgCl₂ = 95.3]

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3.08 g

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Balance the equation in acidic medium:
aMnO₄^-(aq) + bC₂O₄^2-(aq) →cMn²⁺(aq) + dCO₂(g) + eH₂O(l)
Sum of coefficients a+b+c+d+e

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43

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Determine the percentage yield of C₈H₉NO₂ from the reaction of 0.157 g of C₆H₇NO with 0.486 g of C₄H₆O₃ to produce C₈H₉NO₂ and CH₃COOH. After purification, 0.198 g of C₈H₉NO₂ was extracted. [Ar C : 12.O; H=1.0; N=18; O=16.0]

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91.24%

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Calculate the mass (in kg) of water produced from the combustion of 1.0 gallon (3.8 L) of gasoline (C₈H₁₈). The density of gasoline is 0.79 g/mL [Mr C : 12.0; H : 1.0]

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4.27 kg

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Calculate the theoretical yield (in gram) of CO₂ when 4.50 g of HCl is reacted with 15.0 g of CaCO₃ according to the equation: 2HCl + CaCO₃ → CaCl₂ + H2O + CO₂. Options: 2.05 g, 4.12 g, 3.02 g, 2.71 g

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2.71 g

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290.23 mg of ethanol (C₂H₅OH) is reacted with excess oxygen (O₂) to provide 481.11 mg of CO₂. What is the percentage yield of CO₂ in this reaction? Options: 90.0 %, 86.7 %, 67.8 %, 77.8 %

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86.7 %