Question

В воду массой 1,5 кг при температуре 20 градусов Цельсия залили 0,8 кг воды при температуре 100 градусов Цельсия. Какое количество теплоты отдано окружающей среде до момента, когда температура смеси стала 35 градусов Цельсия?

Answer 1

водa массой 1,5 кг - нагревается

Q1= cm1∆Т1

водa массой 0,8 кг - охлаждается

Q2= cm1∆Т2

количество теплоты отдано окружающей среде 

Q=Q1-Q2=cm1∆Т1-cm1∆Т2=c(m1∆Т1-m1∆Т2 )=

=4200(1.5(35-20)-0.8(100-35))=123.9кДж

Answer 2

Для решения этой задачи мы можем использовать формулу для расчета количества теплоты, которое необходимо передать или отдать для изменения температуры вещества:

Q = mcΔT,

где Q - количество теплоты, m - масса вещества, c - удельная теплоемкость вещества, ΔT - изменение температуры.

Для первой порции воды: m1 = 1,5 кг, c1 = 4,186 Дж/(г*С), ΔT1 = (35 градусов Цельсия - 20 градусов Цельсия) = 15 градусов Цельсия.

Q1 = 1,5 кг * 4,186 Дж/(г*С) * 15 градусов Цельсия = 94,185 Дж.

Для второй порции воды: m2 = 0,8 кг, c2 = 4,186 Дж/(г*С), ΔT2 = (35 градусов Цельсия - 100 градусов Цельсия) = -65 градусов Цельсия.

Q2 = 0,8 кг * 4,186 Дж/(г*С) * (-65) градусов Цельсия = -214,64 Дж.

Таким образом, общее количество теплоты, отданное окружающей среде до момента, когда температура смеси стала 35 градусов Цельсия, равно: Q = Q1 + Q2 = 94,185 Дж - 214,64 Дж = -120,455 Дж.

Таким образом, количество теплоты, отданное окружающей среде до момента, когда температура смеси стала 35 градусов Цельсия, равно -120,455 Дж. Отрицательный знак указывает на то, что теплота была отдана окружающей среде.

Answer 3

Calculation of Heat Transfer

To calculate the amount of heat transferred to the surroundings until the temperature of the mixture reaches 35 degrees Celsius, we can use the formula:

Q = m * c * ΔT

Where: - Q is the heat transferred - m is the mass of the substance - c is the specific heat capacity of the substance - ΔT is the change in temperature

In this case, we have two substances: water with a mass of 1.5 kg and water with a mass of 0.8 kg.

Let's calculate the heat transferred for each substance separately and then sum them up.

# Heat Transferred for the First Substance (1.5 kg of Water)

The initial temperature of the first substance is 20 degrees Celsius, and the final temperature is 35 degrees Celsius. The mass of the first substance is 1.5 kg.

To calculate the heat transferred for the first substance, we need to know the specific heat capacity of water. According to the specific heat capacity of water is approximately 4.18 J/g°C.

Converting the mass of the first substance to grams: 1.5 kg = 1500 g

Using the formula Q = m * c * ΔT, we can calculate the heat transferred for the first substance:

Q1 = 1500 g * 4.18 J/g°C * (35°C - 20°C)

# Heat Transferred for the Second Substance (0.8 kg of Water)

The initial temperature of the second substance is 100 degrees Celsius, and the final temperature is 35 degrees Celsius. The mass of the second substance is 0.8 kg.

Using the formula Q = m * c * ΔT, we can calculate the heat transferred for the second substance:

Q2 = 800 g * 4.18 J/g°C * (35°C - 100°C)

# Total Heat Transferred

To find the total heat transferred, we sum up the heat transferred for each substance:

Total Q = Q1 + Q2

Now let's calculate the values.

# Calculation

Using the given values and the formulas mentioned above, we can calculate the heat transferred to the surroundings until the temperature of the mixture reaches 35 degrees Celsius.

For the first substance: - m1 = 1500 g - c1 = 4.18 J/g°C - ΔT1 = 35°C - 20°C

For the second substance: - m2 = 800 g - c2 = 4.18 J/g°C - ΔT2 = 35°C - 100°C

Calculating the heat transferred for each substance:

Q1 = 1500 g * 4.18 J/g°C * (35°C - 20°C) = 1500 g * 4.18 J/g°C * 15°C

Q2 = 800 g * 4.18 J/g°C * (35°C - 100°C) = 800 g * 4.18 J/g°C * (-65°C)

Now, let's calculate the total heat transferred:

Total Q = Q1 + Q2

Please note that the negative sign in Q2 indicates that heat is being transferred from the second substance to the surroundings.

Answer

The amount of heat transferred to the surroundings until the temperature of the mixture reaches 35 degrees Celsius is the sum of the heat transferred for each substance:

Total Q = Q1 + Q2

Substituting the calculated values:

Total Q = (1500 g * 4.18 J/g°C * 15°C) + (800 g * 4.18 J/g°C * (-65°C))

Now you can calculate the total heat transferred using the given values and the formulas provided.