If the standard enthalpy of combustion of octane, C8H18(l) is -5471 kJ/mol, calculate the enthalpy change when 1.00 kg of octane are burned. the molar mass of octane is 114 g/mol

Ethane, C2H6(g) can be made by reaction of hydrogen gas with acetylene, C2H2(g). the standard enthalpies of formation of ethane and acetylene are -84.68 and +226.73 kJ mol-1, respectively. what is the reaction enthalpy for the production of one mole of ethane? Write the balanced chemical equation for the reaction first.

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To calculate the enthalpy change when 1.00 kg of octane (C8H18) is burned, we need to first calculate the number of moles of octane.

Given:
Mass of octane = 1.00 kg
Molar mass of octane (C8H18) = 114 g/mol

Step 1: Convert kg to g
1.00 kg * 1000 g/kg = 1000 g

Step 2: Calculate the number of moles
Number of moles = Mass (g) / Molar mass (g/mol)
Number of moles = 1000 g / 114 g/mol
Number of moles = 8.77 mol (rounded to two decimal places)

Step 3: Calculate the enthalpy change
Enthalpy change = Standard enthalpy of combustion * Number of moles
Enthalpy change = -5471 kJ/mol * 8.77 mol
Enthalpy change = -48013.67 kJ (rounded to two decimal places)

Therefore, the enthalpy change when 1.00 kg of octane is burned is approximately -48013.67 kJ.

To calculate the enthalpy change when 1.00 kg of octane is burned, we need to first convert the mass from kilograms to grams.

Given:
Mass of octane = 1.00 kg = 1000 g
Molar mass of octane (C8H18) = 114 g/mol
Standard enthalpy of combustion of octane = -5471 kJ/mol

Step 1: Calculate the number of moles of octane:
Number of moles = Mass / Molar mass
Number of moles = 1000 g / 114 g/mol
Number of moles ≈ 8.77 mol

Step 2: Use stoichiometry to determine the enthalpy change:
The balanced equation for the combustion of octane is:

2 C8H18(l) + 25 O2(g) -> 16 CO2(g) + 18 H2O(g)

From the balanced equation, we can see that the molar ratio between octane and enthalpy change is 2:5471 kJ/mol.

Enthalpy change = (Number of moles of octane) x (Enthalpy change per mole)
Enthalpy change = 8.77 mol x -5471 kJ/mol
Enthalpy change ≈ -47,890 kJ

Therefore, the enthalpy change when 1.00 kg of octane is burned is approximately -47,890 kJ.