Question

Скільки потрібно енергії для випаровування 2кг льоду через кипіння, взятого за температури -8 градусів. скільки для цього потрібно спалити сухого спирту?

Answer 1

Решение во вложении...................

Answer 2

Calculation of Energy Required to Evaporate 2kg of Ice

To calculate the energy required to evaporate 2kg of ice through boiling, we need to consider the specific heat capacity of ice, the latent heat of fusion, and the latent heat of vaporization.

1. First, we need to calculate the energy required to raise the temperature of the ice from -8 degrees Celsius to its melting point (0 degrees Celsius). The specific heat capacity of ice is approximately 2.09 J/g°C

The mass of the ice is 2kg, which is equivalent to 2000g. Therefore, the energy required to raise the temperature of the ice can be calculated as follows:

Energy = mass * specific heat capacity * temperature change = 2000g * 2.09 J/g°C * (0°C - (-8°C)) = 2000g * 2.09 J/g°C * 8°C = 33,440 J

2. Next, we need to calculate the energy required to melt the ice at its melting point. The latent heat of fusion for ice is approximately 334,000 J/kg

The mass of the ice is 2kg, so the energy required to melt the ice can be calculated as follows:

Energy = mass * latent heat of fusion = 2kg * 334,000 J/kg = 668,000 J

3. Finally, we need to calculate the energy required to vaporize the water at its boiling point. The latent heat of vaporization for water is approximately 2,260,000 J/kg.

The mass of the water is also 2kg, so the energy required to vaporize the water can be calculated as follows:

Energy = mass * latent heat of vaporization = 2kg * 2,260,000 J/kg = 4,520,000 J

Therefore, the total energy required to evaporate 2kg of ice through boiling is the sum of the three calculated energies:

Total Energy = Energy to raise temperature + Energy to melt + Energy to vaporize = 33,440 J + 668,000 J + 4,520,000 J = 5,221,440 J

Energy Required to Burn Dry Alcohol (Ethanol)

To calculate the energy required to burn dry alcohol (ethanol), we need to consider the heat of combustion of ethanol.

The heat of combustion of ethanol is approximately 30.0 kJ/g.

The mass of dry alcohol required to produce the same amount of energy as the evaporation of 2kg of ice can be calculated as follows:

Mass of dry alcohol = Total energy required / Heat of combustion of ethanol = 5,221,440 J / (30.0 kJ/g * 1000 J/kJ) = 174.048 g

Therefore, approximately 174.048 grams of dry alcohol (ethanol) would need to be burned to produce the same amount of energy required to evaporate 2kg of ice through boiling.

Please note that the values used in this calculation are approximate and may vary depending on the specific properties of the substances involved.

I hope this answers your question! Let me know if you need any further clarification.