when a 0.702g sample of a mixture of volatile hydrocarbons is burned in a bomb calorimeter with a heat capacity of 4287 J/C, the temperature rises by 4.72 degrees C. How much energy (in kilojoules) is released during combustion?

q = 4287 J/c x 4.72 = ?

Convert to kJ.

.544

To calculate the energy released during combustion, we can use the formula:

q = m * C * ΔT

where:
q is the energy released (in joules)
m is the mass of the sample (in grams)
C is the heat capacity of the calorimeter (in J/C)
ΔT is the change in temperature (in degrees Celsius)

First, let's convert the mass of the sample to kilograms:

m = 0.702 g = 0.702 * 10^-3 kg

Now, we can substitute the given values into the formula:

q = (0.702 * 10^-3 kg) * (4287 J/C) * (4.72 °C)

Calculating this, we find:

q = 13.065 J

To convert this to kilojoules, divide by 1000:

q = 13.065 J / 1000 = 0.013065 kJ

Therefore, the energy released during combustion is approximately 0.013065 kilojoules.

To find the energy released during combustion, we can use the formula:

Energy released = heat capacity * change in temperature

Given:
- Mass of the sample = 0.702 g
- Heat capacity of the calorimeter = 4287 J/C
- Change in temperature = 4.72 degrees C

First, we need to convert the mass of the sample from grams to kilograms:

Mass of the sample = 0.702 g = 0.702 * 10^-3 kg

Next, we can plug the values into the formula to calculate the energy released:

Energy released = (0.702 * 10^-3 kg) * (4287 J/C) * (4.72 degrees C)

Now we can calculate the energy released:

Energy released = (0.702 * 10^-3 kg) * (4287 J/C) * (4.72 degrees C)
Energy released = 13.024 * 10^-3 J

Finally, we need to convert the energy from joules to kilojoules:

Energy released = 13.024 * 10^-3 J = 13.024 * 10^-3 * 10^-3 kJ
Energy released ≈ 0.013 kJ

Therefore, approximately 0.013 kilojoules of energy is released during combustion.