Methane burns in oxygen according to the equation: CH₄ + 2O₂ → CO₂ + 2H₂O. What volume of oxygen, in cm³, is required to completely burn 50 cm³ of methane? All volumes are measured at the same temperature and pressure.

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Question

Methane burns in oxygen according to the equation: CH₄ + 2O₂ → CO₂ + 2H₂O. What volume of oxygen, in cm³, is required to completely burn 50 cm³ of methane? All volumes are measured at the same temperature and pressure.

Accepted Answer

100 — Award 1 mark for correct answer. The mole ratio of CH₄ : O₂ is 1 : 2. Since equal volumes of gases at the same temperature and pressure contain equal numbers of moles, the volume ratio is also 1 : 2. Therefore, 50 cm³ of CH₄ requires 2 × 50 = 100 cm³ of O₂. A is incorrect because this would be half the required volume. B is incorrect because this suggests a 1:1 ratio. D is incorrect because this is three times the methane volume.

Answer

100

Answer

150

Answer

25

Answer

50

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