Question

Complete combustion of a 0.350 g sample of a compound in a bomb calorimeter releases 14.0 kJ of heat. The bomb calorimeter has a mass of 1.20 kg and a specific heat of 3.55 J/(gi°C). If the initial temperature of the calorimeter is 22.5°C, what is its final temperature? Use q equals m C subscript p Delta T..

Answer 1

Answer:

25.8 °C

Explanation:

The amount of heat released by the compound in a bomb calorimeter is 14.0kJ,

But heat released by the compound will be equal to the heat gained by the calorimeter. 

Heat energy = mass × specific heat × change in temperature.

Therefore;

14000 J = 1200 g × 3.55 ×(x-22.5)

14000 = 4260 (x-22.5)

x-22.5 = 3.286

       x = 25.786

          ≈ 25.9

Therefore, the final temperature is 25.8 °c

Answer 2

Answer:

Its final temperature is 25.8 °C

Explanation:

Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.

There is a direct proportional relationship between heat and temperature. The constant of proportionality depends on the substance that constitutes the body as on its mass, and is the product of the specific heat by the mass of the body. So, the equation that allows calculating heat exchanges is:

Q = c * m * ΔT

where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation (ΔT=Tfinal-Tinitial)

When a body transmits heat there is another that receives it. This is the principle of the calorimeter. Then the heat released by the compound will be equal to the heat obtained by the calorimeter.

In this case, you know:

• Q= 14 kJ= 14,000 J

• c= 3.55  $\frac{J}{g*C}$

• m=1.20 kg= 1200 g (1 kg=1000 g)
• Tfinal= ?
• Tinitial= 22.5 °C

Replacing:

$14,000 J= 3.55 \frac{J}{g*C}*1200 g*(Tfinal-22.5C)$

Solving:

$\frac{14,000J}{3.55\frac{J}{g*C} *1200 g} =T final - 22.5C$

3.3=Tfinal - 22.5 C

3.3 + 22.5=Tfinal

Tfinal= 25.8 °C

Its final temperature is 25.8 °C