Answer:
The molar heat of combustion for butanol is 2.7 *10³ kJ/mol
Explanation:
Step 1: Data given
Temperature change = 4.18 °C
mass of butanol = 3.00 grams
When butanol is burned Temperature change = 20.81 °C
Step 2: Calculate Ccalorimeter
Ccal = 21750J / 4.18 °C = 5203.35 J/ °C
Step 3: Calculate heat generated
Heat generated = 20.81 °C * 5203.35 J/°C = 108281.71 J = 108.28 kJ
Step 4: Calculate moles of butanol
Number of moles = mass / molar mass
Number of moles = 3 grams / 74.123 g/mol = 0.04 moles
Step 5: Calculate Molar heat of combustion
Molar heat of combustion = 108.28 kJ / 0.04 moles = 2707 kJ /mol
The molar heat of combustion for butanol is 2.7 *10³ kJ/mol
