Question

One mole of carbon (12.0 g) in the form of crystalline graphite is burned at 25◦C and 1.000 atm pressure to form CO2(g). All of the heat produced is used to heat a 5100 g bath of liquid water, originally at 25◦C. What is the final temperature of the water bath? The heat of formation of CO2(g) is −393.5 kJ/mol and the specific heat of water is 4.18 J/g/◦C. Answer in units of ◦C

Answer 1

T₂ = 43.46 °C

Step-by-step explanation:

Given that:

The heat of the formation of carbon dioxide = - 393.5 kJ/mol (Negative sign suggests heat loss)

It means that energy released when 1 mole of carbon undergoes combustion = 393.5 kJ = 393500 J

Heat gain by water = Heat lost by the reaction

Thus,

`m_(water)* C_(water)* \Delta T=Q`

For water:

Mass of water = 5100 g

Specific heat of water = 4.18 J/g°C

T₁ = 25 °C

T₂ = ?

Q = 393500 J

So,

`5100* 4.18* (T_2-25)=393500`

T₂ = 43.46 °C