Final answer:
Burning 1.4 moles of ethane produces 4.2 moles of water, which equals 2.52924 × 10²24 molecules of water when calculated using Avogadro's number.
Step-by-step explanation:
When 1.4 moles of ethane (C2H6) are burned, we can use the balanced chemical equation to determine the number of moles of water (H2O) produced. The combustion reaction of ethane is as follows:
2 C2H6 (g) + 7 O2 (g) → 4 CO2 (g) + 6 H2O (g)
According to the stoichiometry of the reaction, 2 moles of ethane produce 6 moles of water. Hence, 1.4 moles of ethane will produce (1.4 moles ethane x (6 moles H2O / 2 moles C2H6)) moles of water. This simplifies to 4.2 moles of water.
Since 1 mole of any substance contains Avogadro's number (6.022 × 1023 particles/molecules), we can calculate the number of water molecules produced by multiplying the moles of H2O by Avogadro's number:
4.2 moles H2O × 6.022 × 1023 molecules/mole = 2.52924 × 1024 molecules of water