Respuesta :
Answer: The final temperature of the water is [tex]33.85^{o}C[/tex].
Explanation:
We know that molar mass of [tex]C_{6}H_{6}[/tex] is 78 g/mol. And, the amount of heat produced when 2 mol of [tex]C_{2}H_{6}[/tex] burns is 6542 KJ.
This means that,
[tex]78 \times 2[/tex] = 156 g of [tex]C_{2}H_{6}[/tex] burns, heat produced is 6542 kJ.
Therefore, heat produced (Q) by burning 7.3 g of [tex]C_{6}H_{6}[/tex] is as follows.
[tex]\frac{6542 \times 7.3 g}{156 g}[/tex]
= 306.13 kJ
or, = 306130 J (as 1 KJ = 1000 J)
For water, mass is given as 5691 g and specific heat capacity of water is 4.186 [tex]J/g^{o}C[/tex].
So, we will calculate the value of final temperature as follows.
Q = [tex]m \times C \times (T_{f} - T_{i})[/tex]
306130 J = [tex]5691 g \times 4.186 J/g^{o}C \times (T_{f} - 21)^{o}C[/tex]
[tex](T_{f} - 21)^{o}C = \frac{306130 J}{23822.53 J/^{o}C}[/tex]
[tex]T_{f}[/tex] = 12.85 + 21
= [tex]33.85^{o}C[/tex]
Thus, we can conclude that the final temperature of the water is [tex]33.85^{o}C[/tex].
