Question

0,7 кг льда взятого при 0 градусов привротили в воду при 45градусов. Сколько теплоты потребовалось для этого?

Answer 1

Q=cm(t2-t1)  Q=2100x0.7x45=66150

Answer 2

Calculating Heat Required to Melt Ice

To calculate the heat required to melt 0.7 kg of ice at 0 degrees Celsius and then raise the resulting water to 45 degrees Celsius, we can use the following steps:

1. Heat to melt the ice: The heat required to melt the ice can be calculated using the formula: \[ Q_1 = m \times L_f \] where \( Q_1 \) is the heat required, \( m \) is the mass of the ice, and \( L_f \) is the specific latent heat of fusion for ice.

2. Heat to raise the temperature of water: The heat required to raise the temperature of the resulting water from 0 degrees Celsius to 45 degrees Celsius can be calculated using the formula: \[ Q_2 = m \times c \times \Delta T \] where \( Q_2 \) is the heat required, \( m \) is the mass of the water, \( c \) is the specific heat capacity of water, and \( \Delta T \) is the change in temperature.

3. Total heat required: The total heat required is the sum of the heat to melt the ice and the heat to raise the temperature of the water: \[ Q_{total} = Q_1 + Q_2 \]

Let's calculate each step using the given values and constants.

Calculation

1. Heat to melt the ice: - Mass of ice, \( m = 0.7 \, \text{kg} \) - Specific latent heat of fusion for ice, \( L_f = 334 \, \text{J/g} \) \[ Q_1 = m \times L_f \]

\[ Q_1 = 0.7 \, \text{kg} \times 334 \, \text{J/g} \]

\[ Q_1 = 234.8 \, \text{kJ} \]

2. Heat to raise the temperature of water: - Change in temperature, \( \Delta T = 45 - 0 = 45 \, \text{°C} \) - Specific heat capacity of water, \( c = 4.18 \, \text{J/g°C} \) \[ Q_2 = m \times c \times \Delta T \]

\[ Q_2 = 0.7 \, \text{kg} \times 4.18 \, \text{J/g°C} \times 45 \, \text{°C} \]

\[ Q_2 = 132.615 \, \text{kJ} \]

3. Total heat required: \[ Q_{total} = Q_1 + Q_2 \] \[ Q_{total} = 234.8 \, \text{kJ} + 132.615 \, \text{kJ} \] \[ Q_{total} = 367.415 \, \text{kJ} \]

Answer

The total heat required to melt 0.7 kg of ice at 0 degrees Celsius and then raise the resulting water to 45 degrees Celsius is approximately 367.415 kJ.