Answer:
c. 300 cal
Explanation:
To calculate the heat, we use the following equation:
heat = m x Cp x ΔT
Where m is the mass of water, Cp is the specific heat of water (which is 1 cal/g.°C) and ΔT is the change in temperature (calculated as the difference between the final T and the initial T).
We have the volume of water (10 ml) but not the mass. As the density of water is 1 g/ml, the mass of water is:
density = mass/volume ⇒ mass = density x volume = 1 g/ml x 10 ml = 10 g
The change in temperature (ΔT) is:
ΔT= Final T - Initial T = 25°C - (-5°C) = 30°C
Finally, we introduce the data to calculate the heat:
heat = 10 g x 1 cal/g.°C x 30°C = 300 cal
Therefore, the correct option is c. 300 cal
