Question

Agatha has 1kg samples of two substance- A and B. Substance A has a higher specific heat capacity than substance B. Both samples cool down by 10C. Which will release more heat - A or B

Answer 1

Answer:

Substance A will release more heat.

Explanation:

Let suppose that both substances experiment an entirely sensible heat process and are incompressible and begin at the same temperature. Physically speaking, specific heat ($c$), measured in kilojoules per kilogram-degree Celsius, can be described by following expression:  

$c = \frac{Q}{m\cdot (T_{f}-T_{o})}$ (1)

Where:

$Q$ - Released heat, measured in kilojoules.

$m$ - Sample mass, measured in kilograms.

$T_{o}$, $T_{f}$ - Initial and final temperatures of the sample, measured in degrees Celsius.

If we know that $c_{A}> c_{B}$, $m_{A} = m_{B}$, $T_{A,o} = T_{B,o}$ and $T_{A,f} = T_{B,f}$, then we have the following inequation:

$\frac{Q_{A}}{m\cdot (T_{A,f}-T_{A,o})} > \frac{Q_{B}}{m\cdot (T_{B,f}-T_{B,o})}$

$Q_{A} > Q_{B}$

Substance A will release more heat.