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A 1.800-g sample of solid phenol (C6H5OH(s)) was burned in a bomb calorimeter whose total heat capacity is 11.66 kJ/?C. The temperature of the calorimeter plus contents increased from 21.36?Cto 26.37?C.Part A

Write a balanced chemical equation for the bomb calorimeter reaction.
Part B:
What is the heat of combustion per gram of phenol?Part C:
Per mole of phenol?

User Mullerivan
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1 Answer

4 votes

Answer:

The balanced chemical equation:


C_6H_5OH(s)+7O_2(g)\rightarrow 6CO_2(g)+3H_2O(g)

Heat of combustion per gram of phenol is 32.454 kJ/g

Heat of combustion per gram of phenol is 3,050 kJ/mol

Step-by-step explanation:


C_6H_5OH(s)+7O_2(g)\rightarrow 6CO_2(g)+3H_2O(g)

Heat capacity of calorimeter = C = 11.66 kJ/°C

Initial temperature of the calorimeter =
T_1= 21.36^oC

Final temperature of the calorimeter =
T_2= 26.37^oC

Heat absorbed by calorimeter = Q


Q=C* \Delta T

Heat released during reaction = Q'

Q' = -Q ( law of conservation of energy)

Energy released on combustion of 1.800 grams of phenol = Q' = -(58.4166 kJ)

Heat of combustion per gram of phenol:


(Q')/(1.800 g)=(-58.4166 kJ)/(1.800 g)=32.454 kJ/g

Molar mass of phenol = 94 g/mol

Heat of combustion per gram of phenol:


(Q')/((1.800 g)/(94 g/mol))=(-58.4166 kJ* 94 g/mol)/(1.800 g)=3,050 kJ/mol

User Ben Hadfield
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