Question

В Калориметр, содержащий некоторую массу воды, впустили пар, взятый при температуре кипения воды. После учтановления теплового равновесия в калориметре находится вода при температуре 60°c. Чему была равна начальная температура воды, если ее масса была в 25 раз больше начальной массы пара?

Answer 1

25*m*c*(t-t0)=m*c*(t1-t)+m*L
25*c*(t-t0)=c*(t1-t)+L
(t-t0)=(t1-t)/25+L/(25*c)
t0=t-(t1-t)/25-L/(25*c)=
t0=60-(100-60)/25-2300000/(25*4200) С =36,495 С ~ 36,5 С - это ответ

Answer 2

Problem Analysis

We are given a calorimeter containing a certain mass of water. Steam at the boiling point of water is introduced into the calorimeter. After reaching thermal equilibrium, the water in the calorimeter is at a temperature of 60°C. We need to determine the initial temperature of the water if its mass was 25 times greater than the initial mass of the steam.

Solution

To solve this problem, we can use the principle of conservation of energy. The heat gained by the water in the calorimeter is equal to the heat lost by the steam.

Let's denote the initial mass of the steam as m1 and the initial temperature of the steam as t1. The mass of the water in the calorimeter is 25 times greater than the initial mass of the steam, so the mass of the water is 25m1. The final temperature of the water is given as 60°C.

Using the principle of conservation of energy, we can write the equation:

Heat gained by water = Heat lost by steam

The heat gained by the water can be calculated using the specific heat capacity of water (c) and the mass of the water (25m1) as:

Q1 = c * (25m1) * (60 - t)

The heat lost by the steam can be calculated using the specific heat capacity of steam (c) and the mass of the steam (m1) as:

Q2 = c * m1 * (t1 - 100)

Since the heat gained by the water is equal to the heat lost by the steam, we can set up the equation:

Q1 = Q2

Substituting the expressions for Q1 and Q2, we get:

c * (25m1) * (60 - t) = c * m1 * (t1 - 100)

Simplifying the equation, we can cancel out the specific heat capacity (c) and the mass of the steam (m1):

25 * (60 - t) = t1 - 100

Solving for t, the initial temperature of the water, we get:

t = (25 * 60 - t1 + 100) / 25

Now we can substitute the given values to find the initial temperature of the water.

Calculation

Given: - Final temperature of the water (t) = 60°C - Mass of the water (25m1) = 25 times the initial mass of the steam

We need to find the initial temperature of the water (t1).

Substituting the given values into the equation, we get:

t = (25 * 60 - t1 + 100) / 25

Simplifying the equation, we have:

60 = (1500 - t1 + 100) / 25

Multiplying both sides of the equation by 25, we get:

1500 - t1 + 100 = 60 * 25

Simplifying further, we have:

1600 - t1 = 1500

Subtracting 1600 from both sides of the equation, we get:

-t1 = -100

Dividing both sides of the equation by -1, we get:

t1 = 100

Therefore, the initial temperature of the water was 100°C.

Answer

The initial temperature of the water, when its mass was 25 times greater than the initial mass of the steam, was 100°C.