Respuesta :
Answer : The [tex]\Delta E[/tex] for the combustion of naphthalene is [tex]5161.25KJ/mole[/tex]
Solution : Given,
Mass of naphthalene = 1.025 g
Initial temperature = [tex]24.25^oC[/tex]
Final temperature = [tex]32.33^oC[/tex]
Specific heat capacity of calorimeter = [tex]5.11KJ/^oC[/tex]
Molar mass of naphthalene = 128 g/mole
First, we have to calculate the heat absorbed, [tex]q[/tex]
Formula used :
[tex]q=c\times \Delta T=c\times (T_{final}-T_{initial})[/tex]
Now put all the given values in this formula, we get
[tex]q=(5.11KJ/^oC)\times (32.33^oCT-24.25^oC)=41.29KJ[/tex]
Now we have to calculate the moles of naphthalene.
Moles of [tex]C_{10}H_{8}[/tex] = [tex]\frac{\text{ Mass of }C_{10}H_{8}}{\text{ Molar mass of }C_{10}H_{8}}=\frac{1.025g}{128g/mole}=0.0080moles[/tex]
Now we have to calculate the [tex]\Delta E[/tex] for combustion of naphthalene.
[tex]\Delta E=\frac{q}{n}[/tex]
where,
q = heat absorbed
n = number of moles
Now put all the values in this formula, we get
[tex]\Delta E=\frac{41.29KJ}{0.0080moles}=5161.25KJ/mole[/tex]
Therefore, the [tex]\Delta E[/tex] for the combustion of naphthalene is [tex]5161.25KJ/mole[/tex]
