Organic hydrogenation reactions, in which H2 and an "unsaturated" organic compound combine, are used in the food, fuel, and polymer industries. In the simplest case, ethene (C2H4) and H2 form ethane (C2H6). If 124 kJ is given off per mole of C2H4 reacting, how much heat is released when 14.6 kg of C2H6 forms?
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To determine the amount of heat released when 14.6 kg of C2H6 forms, we need to first calculate the number of moles of ethane (C2H6) using its molar mass.
The molar mass of ethane (C2H6) can be calculated by adding the atomic masses of carbon (C) and hydrogen (H).
Molar mass of C = 12.01 g/mol
Molar mass of H = 1.01 g/mol
Molar mass of C2H6 = (2 * Molar mass of C) + (6 * Molar mass of H)
= (2 * 12.01 g/mol) + (6 * 1.01 g/mol)
= 24.02 g/mol + 6.06 g/mol
= 30.08 g/mol
Now, we can calculate the number of moles of C2H6 by dividing the given mass (14.6 kg) by the molar mass.
Number of moles of C2H6 = (Mass of C2H6) / (Molar mass of C2H6)
= (14.6 kg) / (30.08 g/mol)
Note that we need to convert the mass from kg to g, and then divide by the molar mass to get the answer in moles.
Number of moles of C2H6 = (14.6 kg * 1000 g/kg) / (30.08 g/mol)
= 486,666.67 g / 30.08 g/mol
≈ 16,165.27 mol
Now that we know the number of moles of C2H6, we can calculate the heat released using the given energy change of -124 kJ/mol.
Heat released = (Number of moles of C2H6) * (Energy change per mole)
= (16,165.27 mol) * (-124 kJ/mol)
Note that the negative sign indicates that heat is being released during the reaction.
Heat released = - 2006105.48 kJ
Therefore, approximately 2,006,105.48 kJ of heat is released when 14.6 kg of C2H6 forms.