Question

How much heat would be released by 1.3 kg of water if it's temperature went from 295 k to 274 k

Answer 1

Answer: The energy released will be 114.223 kJ.

Explanation:

To calculate the amount of heat released, we use the formula:

$Q= m\times c\times \Delta T$

Q = heat gained  or released

m = mass of the substance = 1.3kg = 1300 g   (Conversion factor: 1kg = 1000g)

c = heat capacity of water = 4.184 J/g K

$\Delta T={\text{Change in temperature}}=(274-295)K=-21K$

Putting values in above equation, we get:  

$Q=1300g\times 4.184J/gK\times (-21)K$

Q = -114223 Joules  = -114.223 kJ      (Conversion Factor: 1kJ = 1000J)

Negative sign implies heat released.

Hence, heat released by 1.3 kg of water is 114.223kJ.