Respuesta :
The question is incomplete, the complete question is
The following equation is the balanced combustion reaction for C6H6
[tex]2C_6H_6(l)+15O_2(g) \rightarrow 12CO_2(g)+6H_2O(l)+6542 kJ[/tex]
If 7.400 g of [tex]C_6H_6[/tex] is burned and the heat produced from the burning is added to 5691 g of water at 21°C. What is the final temperature of the water?
Answer:
34.45°C is the final temperature of the water.
Explanation:
Moles of benzene = [tex]\frac{7.400 g}{78 g/mol}=0.09487 mol[/tex]
According to reaction, 2 moles of benzene on combustion gives 6542 kJ of heat. Then 0.09487 moles of benzene will give:
[tex]\frac{1}{2}\times 6542 kJ\times 0.09487 mol=310.325 kJ[/tex]
Heat added to water = Q = 310.325 kJ = 310,325 J
(1 kJ = 1000 J)
Specific heat of water = C = [tex]4.18 J/g^oC[/tex]
Mass of the water = m = 5691 g
Initial temperature of the water =[tex]T_1[/tex] = 21°C
Final temperature of the water =[tex]T_2[/tex] =?
Change in temperature of the substance =ΔT =[tex]T_2-T_1[/tex]
[tex]Q=mc\times \Delta (T_2-T_1)[/tex]
[tex]310,325 J=5691 g\times 4.18 J/g^oC\times (T_2-21^oC)[/tex]
[tex]T_2=34.45^oC[/tex]
34.45°C is the final temperature of the water.
Answer:
The final temperature of the water is 34.0 °C
Explanation:
Step 1: Data given
Mass of C6H6 burned = 7.400 grams
Mass of water = 5691 grams
Temperature of water = 21 °C
Specific heat of water = 4.184 K/g°C
2C6H6+15O2→12CO2+6H20+6542KJ
Heat released with combustion of C6H6 = 6542KJ
Step 2: Calculate moles of C6H6
Moles C6H6 = mass C6H6 / molar mass C6H6
Moles C6H6 = 7.400 grams / 78.11 g/mol
Moles C6H6 = 0.09474
Step 3: Calculate heat transfered
Q = 0.09474 moles * 6542 kJ/2 mol = 309.89 kJ
Step 3: Calculate finam temperature
Q = m * c * ΔT
⇒ with Q = the heat transfered =309.9 kJ = 309890 J
⇒ with m = the mass of water = 5691 grams
⇒ with c = the specific heat of water = 4.184 J/g°C
⇒ with ΔT = The change in temperature
ΔT = Q /(m*c)
ΔT = 309890 / ( 5691 * 4.184)
ΔT =13.0 °C
Step 4: Calculate the final temperature
T2 = T1 + ΔT
T2 = 13.0 + 21.0°C
T2 = 34.0 °C
The final temperature of the water is 34.0 °C
