Question

500cm3 of water is to be jeated from room temperature 28oc to 100oc in order to prepare ahot cup pf coffee. What os the minimum heat required

Answer 1

Answer:

The minimum heat required is 171626 joules.  

Explanation:

By First Law of Thermodynamics, the amount of heat ($Q$), in joules, is equal to the change in internal energy of water. The minimum heat required is the sensible heat necessary to heat up the water. That is:

$Q = \rho\cdot V \cdot c\cdot \Delta T$ (1)

Where:

$\rho$ - Density of water, in kilograms per cubic meter.

$V$ - Volume of water, in cubic meters.

$c$ - Specific heat of water, in joules per kilogram-degree Celsius.

$\Delta T$ - Change in temperature, in degrees Celsius.

If we know that $\rho = 1000\,\frac{kg}{m^{3}}$, $V = 5\times 10^{-4}\,m^{3}$, $c = 4186\,\frac{J}{kg\cdot ^{\circ}C}$ and $\Delta T = 82\,^{\circ}C$, then the minimum heat required is:

$Q = 171626\,J$

The minimum heat required is 171626 joules.