Question

На спиртівку ставлять сталевий кухоль з водою при температурі 12 градусів. Який об'єм спирту потрібно спалити, щоб довести воду до кипіння? Маса кухля дорівнює 100 грам, води- 200 грам, ККД спиртівки становить 25%. Помогите срочно!!!​

Answer 1

Ответ:

11 г

Объяснение:

Answer 2

Calculation of the Volume of Alcohol Needed to Boil Water

To calculate the volume of alcohol needed to boil water, we need to consider the specific heat capacity of water, the initial and final temperatures, and the efficiency of the alcohol burner.

Given: - Initial temperature of water (T1) = 12 degrees Celsius - Final temperature of water (T2) = 100 degrees Celsius (boiling point) - Mass of alcohol burner (m1) = 100 grams - Mass of water (m2) = 200 grams - Efficiency of alcohol burner (η) = 25% (0.25)

To find the volume of alcohol needed, we can follow these steps:

1. Calculate the heat energy required to raise the temperature of water from T1 to T2: - Heat energy (Q) = mass of water (m2) * specific heat capacity of water * change in temperature - Specific heat capacity of water = 4.18 J/g°C - Change in temperature = T2 - T1

2. Calculate the heat energy produced by burning the alcohol: - Heat energy produced (Q') = efficiency of alcohol burner * mass of alcohol burner * heat of combustion of alcohol

3. Equate the heat energy required to the heat energy produced: - Q = Q'

4. Solve for the volume of alcohol (V) using the equation: - V = Q' / (density of alcohol * heat of combustion of alcohol)

Let's calculate the volume of alcohol needed using the given values:

1. Calculate the heat energy required to raise the temperature of water: - Change in temperature = 100°C - 12°C = 88°C - Heat energy (Q) = 200g * 4.18 J/g°C * 88°C = 73504 J

2. Calculate the heat energy produced by burning the alcohol: - Heat energy produced (Q') = 0.25 * 100g * heat of combustion of alcohol

3. Equate the heat energy required to the heat energy produced: - Q = Q'

4. Solve for the volume of alcohol (V): - V = Q' / (density of alcohol * heat of combustion of alcohol)

Unfortunately, the specific heat capacity of alcohol, as well as the heat of combustion and density of alcohol, are not provided in the question. To proceed with the calculation, we would need this additional information.

Please provide the specific heat capacity of alcohol, the heat of combustion of alcohol, and the density of alcohol, and I will be happy to assist you further.