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Correct Answer: D
Correct Answer: D
Method / Topic: General Chemistry
The correct option matches the required rule and the given information.
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Correct Answer: D
Method / Topic: General Chemistry
At fixed temperature and pressure, Avogadro's law states that gas volume is directly proportional to the number of gas moles. The reaction stoichiometry is unchanged, so doubling the amount of decomposed H2O2 doubles the amount of O2. Thus the volume changes from 24.6 mL to 2 × 24.6 = 49.2 mL. This result follows from the balanced chemical relationship and the stated conditions; no unstated biological assumption is needed. On MCAT chemistry problems, first identify the governing principle, write the relevant equation with units, and only then substitute values. Check whether the
prevents dosage, dilution, and preparation errors.
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PASSAGE 2 — HYDROGEN PEROXIDE DECOMPOSITION Hydrogen peroxide decomposes as 2H2O2(aq) → 2H2O(l) + O2(g). In one trial at 298 K and 1.00 atm, a catalyst causes a sample to release 24.6 mL of O2. Use R = 0.0821 L·atm·mol−1·K−1. In a separate kinetics experiment, the H2O2 concentration falls from 0.800 M to 0.400 M in 10 minutes and from 0.400 M to 0.200 M during the next 10 minutes. QUESTION 4: At the same temperature and pressure, what O2 volume would be produced if twice as many moles of H2O2 decomposed completely?
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Correct Answer: D
Method / Topic: General Chemistry
The correct option matches the required rule and the given information.
Short Explanation
Detailed Explanation
Correct Answer: D
Method / Topic: General Chemistry
At fixed temperature and pressure, Avogadro's law states that gas volume is directly proportional to the number of gas moles. The reaction stoichiometry is unchanged, so doubling the amount of decomposed H2O2 doubles the amount of O2. Thus the volume changes from 24.6 mL to 2 × 24.6 = 49.2 mL. This result follows from the balanced chemical relationship and the stated conditions; no unstated biological assumption is needed. On MCAT chemistry problems, first identify the governing principle, write the relevant equation with units, and only then substitute values. Check whether the
prevents dosage, dilution, and preparation errors.
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