Question

How much energy must be absorbed by a 150 g sample of ice at 0.0 degrees celcius that metls and then warms to 25.0 degrees celcius?

Answer 1

1. How much energy must be absorbed by a 150 g sample of ice at 0.0 degrees Celsius that melts and then warms to 25.0 degrees Celsius?

**Solution.**

$$Q_1 = m \cdot \lambda$$ $$Q_2 = c \cdot m \cdot (t - t_0)$$ $$E = Q_1 + Q_2 = m \cdot \lambda + c \cdot m \cdot (t - t_0)$$

Given: $m = 0.15 \, \text{kg}$, $t_0 = 0^\circ \text{C}$, $t = 25^\circ \text{C}$, $t - t_0 = 25 \, \text{K}$, $\lambda = 335000 \, \frac{\text{J}}{\text{kg}}$, $c = 4183 \, \frac{\text{J}}{\text{kg} \cdot \text{K}}$

Find: $E - ?$

$$E = 0.15 \, \text{kg} \cdot 335000 \, \frac{\text{J}}{\text{kg}} + 4183 \, \frac{\text{J}}{\text{kg} \cdot \text{K}} \cdot 0.15 \, \text{kg} \cdot 25 \, \text{K} \approx 66 \, \text{kJ}$$

**Answer:**

$$E = 66 \, \text{kJ}$$