Liquid heptane, C₇H₁₆, burns in oxygen gas to yield carbon dioxide and water. What mass of water is produced when 15.0 mL of heptane burns completely? (density of heptane = 0.6838 g/mL) A)14.8 g B)2.70 g C)31.6 g D)1.85 g E)21.6 g

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Quizplus · Accepted Answer

15.0 mL of heptane has a mass of 15.0 mL * 0.6838 g/mL = 10.26 g. The balanced chemical equation for the combustion of heptane is:C7H16 + 11O2 -> 7CO2 + 8H2OFrom the balanced chemical equation, we can see that 1 mole of heptane reacts with 8 moles of water. The molar mass of heptane is 100.21 g/mol, so 10.26 g of heptane is equal to 10.26 g / 100.21 g/mol = 0.1024 mol. Therefore, the mass of water produced is 0.1024 mol * 18.02 g/mol = 1.85 g.

Liquid Heptane, C7H16, Burns in Oxygen Gas to Yield Carbon

Liquid Heptane, C₇H₁₆, Burns in Oxygen Gas to Yield Carbon