Help with enthalpy?

a student designed a calormetric experiment to determine the molar heat of combustion of paraffin C25 H52, in a candle. after performing the experiment, the student recorded these data:

Mass of Al(s) calorimeter=16.0g

Mass of water ane calorimeter =410.0g

initial temp of water=20.0(deg)C

final temp of water=35.5(deg)C

initial mass of candle=25.7g

final mass of candle=23.5g

Based on the data given, calculate the molar heat (enthalpy) of combustion of paraffin. Assume that only the calorimeter absorbs heat. please show all pertinent formulas and calculations

Help with enthalpy?soap opera

C25H52 ==>

25*12.011 + 52*1.0079 = 352.6858 g/mol

Specific heats:

Al: 0.897 J/g°C

H20: 4.184 J/g°C

Paraffin: 2.5 J/g°C

mass burned: 2.2 g

?T = 15°C

Ignoring the unburned mass of the candle,

H = (15°C)[(16.0 g)(0.897 J/g°C) + (410.0 g)(4.184 J/g°C)](352.6858 g/mol)/(2.2 g) ≈ 4,159,589 J/mol ≈ 4,160 kJ/mol

If the unburned candle is added in,

H ≈ 4,300 kJ/mol

Help with enthalpy?

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