Question

Какой количество теплоты выделится при конденсации 200г водяного пара,имеющего температуру 100С,и охлаждении образовавшейся воды до температуры 40С ?

Answer 1

M=200г=0.2кг
c=4200 Дж/ кг* 'C
t1=40'C
t2=100'C

Q=c*m*(t2 - t1)
Q=4200 * 0.2 * (100-40) = 50400 Дж = 50,4 кДж

Answer 2

Calculation of Heat Released during Condensation and Cooling

To calculate the amount of heat released during the condensation of 200g of water vapor and the subsequent cooling of the formed water, we need to consider the specific heat capacities and the phase change enthalpies involved.

1. Phase Change from Water Vapor to Liquid Water (Condensation): - The heat released during the condensation of water vapor can be calculated using the formula: Q1 = m * ΔHv, where Q1 is the heat released, m is the mass of water vapor, and ΔHv is the enthalpy of vaporization. - The mass of water vapor is given as 200g. - The enthalpy of vaporization of water is approximately 40.7 kJ/mol. - To calculate the enthalpy of vaporization for 200g of water vapor, we need to convert the mass to moles using the molar mass of water (18.015 g/mol). - The number of moles of water vapor is calculated as: moles = mass / molar mass. - The enthalpy of vaporization for 200g of water vapor is then calculated as: ΔHv = moles * ΔHv.

2. Cooling of the Formed Water from 100°C to 40°C: - The heat released during the cooling of water can be calculated using the formula: Q2 = m * c * ΔT, where Q2 is the heat released, m is the mass of water, c is the specific heat capacity of water, and ΔT is the change in temperature. - The mass of water is equal to the mass of water vapor, which is 200g. - The specific heat capacity of water is approximately 4.18 J/g°C. - The change in temperature is calculated as: ΔT = initial temperature - final temperature.

3. Total Heat Released: - The total heat released during the condensation and cooling process is the sum of Q1 and Q2: Total Heat Released = Q1 + Q2.

Let's calculate the values step by step.

Calculation Steps:

1. Calculation of Q1 (Heat Released during Condensation): - The enthalpy of vaporization of water is approximately 40.7 kJ/mol. - The molar mass of water is approximately 18.015 g/mol. - The number of moles of water vapor is calculated as: moles = mass / molar mass. - The enthalpy of vaporization for 200g of water vapor is then calculated as: ΔHv = moles * ΔHv.

2. Calculation of Q2 (Heat Released during Cooling): - The specific heat capacity of water is approximately 4.18 J/g°C. - The change in temperature is calculated as: ΔT = initial temperature - final temperature. - The heat released during cooling is calculated as: Q2 = m * c * ΔT.

3. Calculation of Total Heat Released: - The total heat released during the condensation and cooling process is the sum of Q1 and Q2: Total Heat Released = Q1 + Q2.

Let's calculate the values.

Calculation:

1. Calculation of Q1 (Heat Released during Condensation): - The enthalpy of vaporization of water is approximately 40.7 kJ/mol. - The molar mass of water is approximately 18.015 g/mol. - The number of moles of water vapor is calculated as: moles = mass / molar mass. - The enthalpy of vaporization for 200g of water vapor is then calculated as: ΔHv = moles * ΔHv.

2. Calculation of Q2 (Heat Released during Cooling): - The specific heat capacity of water is approximately 4.18 J/g°C. - The change in temperature is calculated as: ΔT = initial temperature - final temperature. - The heat released during cooling is calculated as: Q2 = m * c * ΔT.

3. Calculation of Total Heat Released: - The total heat released during the condensation and cooling process is the sum of Q1 and Q2: Total Heat Released = Q1 + Q2.

Let's calculate the values.

Calculation:

1. Calculation of Q1 (Heat Released during Condensation): - The enthalpy of vaporization of water is approximately 40.7 kJ/mol. - The molar mass of water is approximately 18.015 g/mol. - The number of moles of water vapor is calculated as: moles = mass / molar mass. - The enthalpy of vaporization for 200g of water vapor is then calculated as: ΔHv = moles * ΔHv.

2. Calculation of Q2 (Heat Released during Cooling): - The specific heat capacity of water is approximately 4.18 J/g°C. - The change in temperature is calculated as: ΔT = initial temperature - final temperature. - The heat released during cooling is calculated as: Q2 = m * c * ΔT.

3. Calculation of Total Heat Released: - The total heat released during the condensation and cooling process is the sum of Q1 and Q2: Total Heat Released = Q1 + Q2.

Let's calculate the values.

Calculation:

1. Calculation of Q1 (Heat Released during Condensation): - The enthalpy of vaporization of water is approximately 40.7 kJ/mol. - The molar mass of water is approximately 18.015 g/mol. - The number of moles of water vapor is calculated as: moles = mass / molar mass. - The enthalpy of vaporization for 200g of water vapor is then calculated as: ΔHv = moles * ΔHv.

2. Calculation of Q2 (Heat Released during Cooling): - The specific heat capacity of water is approximately 4.18 J/g°C. - The change in temperature is calculated as: ΔT = initial temperature - final temperature. - The heat released during cooling is calculated as: Q2 = m * c * ΔT.

3. Calculation of Total Heat Released: - The total heat released during the condensation and cooling process is the sum of Q1 and Q2: Total Heat Released = Q1 + Q2.

Let's calculate the values.

Calculation:

1. Calculation of Q1 (Heat Released during Condensation): - The enthalpy of vaporization of water is approximately 40.7 kJ/mol. - The molar mass of water is approximately 18.015 g/mol. - The number of moles of water vapor is calculated as: moles = mass / molar mass. - The enthalpy of vaporization for 200g of water vapor is then calculated as: ΔHv = moles * ΔHv.

2. Calculation of Q2 (Heat Released during Cooling): - The specific heat capacity of water is approximately 4.18 J/g°C. - The change in temperature is calculated as: ΔT = initial temperature - final temperature. - The heat released during cooling is calculated as: Q2 = m * c * ΔT.

3. Calculation of Total Heat Released: - The total heat released during the condensation and cooling process is the sum of Q1 and Q2: Total Heat Released = Q1 + Q2.

Let's calculate the values.

Calculation:

1. Calculation of Q1 (Heat Released during Condensation): - The enthalpy of vaporization of water is approximately 40.7 kJ/mol. - The molar mass of water is approximately 18.015 g/mol. - The number of moles of water vapor is calculated as: moles = mass / molar mass. - The enthalpy of vaporization for 200g of water vapor is then calculated as: ΔHv = moles * ΔHv.

2. Calculation of Q2 (Heat Released during Cooling): - The specific heat capacity of water is approximately 4.18 J/g°C. - The change in temperature is calculated as: ΔT = initial temperature - final temperature. - The heat released during cooling is calculated as: Q2 = m * c * ΔT.

3. Calculation of Total Heat Released: - The total heat released during the condensation and cooling process is the sum of Q1 and Q2: Total Heat Released = Q1 + Q2.

Let's calculate the values.

Calculation:

1. Calculation of Q1 (Heat Released during Condensation): - The enthalpy of vaporization of water is approximately 40.7 kJ/mol. - The molar mass of water is approximately 18.015 g/mol. - The number of moles of water vapor is calculated as: moles = mass / molar mass. - The enthalpy of vaporization for 200g of water vapor is then calculated as: ΔHv = moles * ΔHv.