The balanced combustion reaction for c6h6 is 2c6h6(l)+15o2(g)⟶12co2(g)+6h2o(l)+6 542 kj if 6.200 g c6h6 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?

The final temperature of the water : 31.916 °C

The law of conservation of energy can be applied to heat changes, i.e. the heat received / absorbed is the same as the heat released

Q in = Q out

Heat can be calculated using the formula:

Q = heat, J

m = mass, g

c = specific heat, joules / g ° C

∆T = temperature difference, ° C / K

From reaction:

2C₆H₆ (l) + 15O₂ (g) ⟶12CO₂ (g) + 6H₂O (l) +6542 kJ, heat released by +6542 kJ to burn 2 moles of C₆H₆

If there are 6,200 g of C₆H₆ then the number of moles:

mol = mass: molar mass C₆H₆

mol = 6.2: 78

mol C6H6 = 0.0795

so the heat released in combustion 0.0795 mol C6H6:

the heat produced from the burning is added to 5691 g of water at 21 ∘ C

So :

Q = m . c . ∆T  (specific heat of water = 4,186 joules / gram ° C)

260044.5 = 5691 . 4.186.∆T

the difference between temperature and heat  

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Specific heat  

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relationships among temperature, heat, and thermal energy.  

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When heat is added to a substance  

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the answer is either b or c