The value of delta H for the reaction below is -6536 kJ. ____kJ of heat released in the combutsion of 16.0g of C6H6.
2C6H6(l) + 15O2(g) yield 12CO2(g) + 6H2O
First, Determine the number of moles you have of C6H6 (16 g / molar mass (78)) = .206 Moles C6H6
Now its good ol stoichiometry
Using the formula given
2 moles of C6H6 produce the -6536 kJ
.206 C6H6 * -6536kJ / 2 moles C6H6 = -673.208 (or so)
To determine the amount of heat released in the combustion of 16.0 g of C6H6, we first need to calculate the moles of C6H6 using its molar mass.
1. Calculate the molar mass of C6H6 (benzene):
C6H6: (6 * atomic mass of C) + (6 * atomic mass of H)
= (6 * 12.01 g/mol) + (6 * 1.01 g/mol)
= 72.06 g/mol + 6.06 g/mol
= 78.12 g/mol
2. Calculate the moles of C6H6:
Moles = mass / molar mass
Moles = 16.0 g / 78.12 g/mol
Moles ≈ 0.205 mol
Now that we know the number of moles of C6H6, we can use the stoichiometry of the balanced equation to relate it to the amount of heat released.
In the balanced equation:
2C6H6(l) + 15O2(g) → 12CO2(g) + 6H2O
The balanced equation shows that for every 2 moles of C6H6, 6536 kJ of heat is released. Therefore, we can set up a ratio to calculate the amount of heat released when 0.205 moles of C6H6 is combusted.
3. Calculate the amount of heat released:
Heat released = (Delta H) * (moles of C6H6 combusted) / (moles of C6H6 in balanced equation)
Heat released = -6536 kJ * (0.205 mol) / (2 mol)
Heat released ≈ -670 kJ (rounded to three significant figures)
Therefore, approximately -670 kJ of heat is released in the combustion of 16.0 g of C6H6.
To determine the amount of heat released in the combustion of 16.0g of C6H6 (benzene), we need to use the provided enthalpy change value (ΔH) of the equation and apply stoichiometry.
Step 1: Calculate the molar mass of C6H6
The molar mass of C6H6 can be obtained by adding up the atomic masses of its constituent elements. In this case:
Molar mass of C6H6 = 6(C) + 6(H) = 12.01 g/mol + 1.01 g/mol = 78.11 g/mol
Step 2: Determine the number of moles of C6H6
Number of moles = mass / molar mass
Number of moles = 16.0 g / 78.11 g/mol
Step 3: Use stoichiometry to find the amount of heat released
Using the balanced equation:
2C6H6(l) + 15O2(g) → 12CO2(g) + 6H2O
From the equation, we can see that 2 moles of C6H6 release -6536 kJ of heat. Therefore, 1 mole of C6H6 releases (−6536 kJ / 2 mol) = -3268 kJ of heat.
To find the amount of heat released by 16.0g of C6H6, we multiply its moles (from Step 2) by the heat released per mole.
Amount of heat = number of moles × heat per mole
Amount of heat = (16.0 g / 78.11 g/mol) × (-3268 kJ/mol)
Calculating the above expression will give us the amount of heat released in kJ when 16.0g of C6H6 is combusted.
6536 kJ x (16.0/2*molar mass C6H6
dH is -that number. Or it is correct to say that numberr of kJ is released as heat.