Question

Какое количество теплоты необходимо в пар эфира массой 20 г, взятого при температуре 15°С

Answer 1

Температура кипения эфира равна 36°C.
Он взят при t = 15°C
Поэтому нам для начала нужно нагреть эфир на 21°С.
Количество теплоты, которое для этого потребуется: Q1 = c*m*21°C = 
3340 Дж/(кг*°С)*0,02кг*21 = 1402,8 Дж
Теперь мы испаряем эфир
Для этого потребуется энергия равная Q2 = L*m = 4*10⁵ Дж/кг * 0,02 кг = 
= 8000 Дж.
Теперь остается сложить Q1 и Q2: Q1 + Q2 = 9402,8 Дж

Answer 2

Calculating Heat Energy Required to Vaporize Ether

To calculate the amount of heat energy required to vaporize ether, we can use the formula:

Q = m * L

Where: - Q = heat energy required (in joules) - m = mass of the substance (in grams) - L = latent heat of vaporization (in joules/gram)

Given: - m = 20 g - Initial temperature (t1) = 15°C - Final temperature (t2) = boiling point of ether (which is approximately 34.6°C)

First, we need to calculate the heat energy required to raise the temperature of the ether from 15°C to its boiling point, and then the heat energy required for the phase change (vaporization).

Calculating Heat Energy to Raise Temperature

The formula to calculate the heat energy required to raise the temperature of a substance is:

Q1 = c * m * Δt

Where: - Q1 = heat energy required to raise the temperature (in joules) - c = specific heat capacity of the substance (in joules/gram°C) - m = mass of the substance (in grams) - Δt = change in temperature (in °C)

The specific heat capacity of ether is not provided in the search results. However, we can use an approximate value for the specific heat capacity of ether, which is around 0.5 J/g°C.

Using the given values: - c ≈ 0.5 J/g°C - m = 20 g - Δt = (34.6°C - 15°C) = 19.6°C

We can calculate Q1 using the formula.

Calculating Latent Heat of Vaporization

The latent heat of vaporization (L) for ether is not provided in the search results. However, the latent heat of vaporization for ether is approximately 360 J/g.

Using the given value: - L ≈ 360 J/g

Calculating Total Heat Energy Required

Now, we can calculate the total heat energy required (Q) by adding the heat energy required to raise the temperature (Q1) to the heat energy required for the phase change (vaporization) (Q2).

Q = Q1 + Q2

Where: - Q1 = heat energy required to raise the temperature - Q2 = heat energy required for vaporization

Let's calculate Q1 and Q2 using the provided values and the formulas mentioned above.