Question

Какое количество теплоты выделится 8 кг водяного пара, взятого при температуре 100 градусов?

Answer 1

3360кДж выделяется количество теплоты

Answer 2

Calculating the Heat Released by 8 kg of Water Vapor at 100 Degrees Celsius

To calculate the amount of heat released by 8 kg of water vapor at 100 degrees Celsius, we can use the formula:

Q = m * (L + C * (t - t0))

Where: - Q = heat released - m = mass of the substance - L = latent heat - C = specific heat - t = final temperature - t0 = initial temperature

Given: - m = 8 kg - t = 100 degrees Celsius - t0 = 0 degrees Celsius (since it's water vapor)

We can calculate the heat released step by step using the specific heat and latent heat of water vapor.

First, we calculate the heat released due to the change in temperature using the specific heat: Q1 = C * m * (t - t0)

Then, we calculate the heat released due to the phase change from vapor to liquid using the latent heat: Q2 = L * m

Finally, the total heat released is the sum of Q1 and Q2: Q = Q1 + Q2

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

Calculations

1. Heat released due to the change in temperature: - C = 4200 J/(kg·°C) (specific heat of water vapor). - m = 8 kg - t = 100°C - t0 = 0°C - Q1 = C * m * (t - t0)

Using the formula: Q1 = 4200 * 8 * (100 - 0) Q1 = 3360000 J

2. Heat released due to the phase change from vapor to liquid: - L = 23 * 10^5 J/kg (latent heat of vaporization of water). - m = 8 kg - Q2 = L * m

Using the formula: Q2 = 23 * 10^5 * 8 Q2 = 18400000 J

3. Total heat released: Q = Q1 + Q2 Q = 3360000 + 18400000 Q = 21760000 J

Answer

The total amount of heat released by 8 kg of water vapor, taken at 100 degrees Celsius, is 21760000 joules.