Question

В алюминиевой кастрюле массой 1.5 кг находится 800 г воды при комнатной температуре (20 градусов ). Сколько Кипятка нужно долить в кастрюлю , чтобы получить воду температурой 45 градусов

Answer 1

 mк - масса кипятка, са - теплоёмкость алюминия,  mак - масса кастрюли, Δt1 - изменение темп. кипятка,  Δt2 - изменение темп. воды Q отд=Q получ;cв · mк · Δt1 = cа · mак · Δt2 + cв · mв · Δt2mк = (cа · mак · Δt2 + cв · mв · Δt2) /  (cв · Δt1) ≈ 0,51 кг

Answer 2

Calculation of Additional Boiling Water Needed

To calculate the amount of boiling water needed to achieve a water temperature of 45 degrees Celsius in an aluminum pot weighing 1.5 kg with 800 g of water at room temperature (20 degrees Celsius), we can use the principle of heat transfer.

The formula for heat transfer is:

Q = mcΔT

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 want to find the amount of boiling water (m2) needed to raise the temperature of the initial water (m1) from 20 degrees Celsius to 45 degrees Celsius.

Let's assume the specific heat capacity of water is 4.18 J/g°C.

Using the formula, we can calculate the heat transferred from the boiling water to the initial water:

Q1 = m1 * c * ΔT1

Q2 = m2 * c * ΔT2

Since the heat transferred from the boiling water (Q2) is equal to the heat gained by the initial water (Q1), we can set up the equation:

m1 * c * ΔT1 = m2 * c * ΔT2

Substituting the given values: - m1 = 800 g - c = 4.18 J/g°C - ΔT1 = 45°C - 20°C = 25°C - ΔT2 = 100°C - 45°C = 55°C

We can solve for m2:

800 g * 4.18 J/g°C * 25°C = m2 * 4.18 J/g°C * 55°C

Simplifying the equation:

20,900 J = m2 * 229.9 J

m2 = 20,900 J / 229.9 J

m2 ≈ 90.9 g

Therefore, approximately 90.9 grams of boiling water need to be added to the aluminum pot to raise the temperature of the initial water from 20 degrees Celsius to 45 degrees Celsius.

Please note that this calculation assumes no heat loss to the surroundings and that the specific heat capacity of water remains constant over the temperature range.