Question

Парциональное давление водяного пара в атмосфере при 18(гр)С, давлении 1,43 кНа. Найдите влажность воздуха.

Answer 1

По таблице находим давление насыщенного пара при 18С
Pн=2,07 кПа
ф=p*100%/pн=1,43*1005/2,07=69%

Answer 2

Calculating Air Humidity at 18°C and 1.43 kPa

To calculate the air humidity at 18°C and 1.43 kPa, we can use the concept of partial pressure and the saturation vapor pressure at the given temperature.

Step 1: Calculate the Saturation Vapor Pressure

The saturation vapor pressure at 18°C can be calculated using the Antoine equation or obtained from a vapor pressure table. For 18°C, the saturation vapor pressure is approximately 1.7 kPa.

Step 2: Calculate the Partial Pressure of Water Vapor

The partial pressure of water vapor can be calculated using the formula: \[ \text{Partial Pressure of Water Vapor} = \text{Saturation Vapor Pressure} \times \text{Relative Humidity} \]

Given that the total pressure is 1.43 kPa, we can use the partial pressure of water vapor to find the relative humidity.

Step 3: Calculate the Relative Humidity

The relative humidity can be calculated using the formula: \[ \text{Relative Humidity} = \frac{\text{Partial Pressure of Water Vapor}}{\text{Saturation Vapor Pressure}} \times 100 \]

By rearranging the formula, we can solve for the relative humidity.

Let's calculate the relative humidity using the given values.

\[ \text{Partial Pressure of Water Vapor} = 1.43 \, \text{kPa} - \text{Partial Pressure of Dry Air} \]

\[ \text{Relative Humidity} = \frac{\text{Partial Pressure of Water Vapor}}{\text{Saturation Vapor Pressure}} \times 100 \]

Calculating Relative Humidity

\[ \text{Partial Pressure of Water Vapor} = 1.43 \, \text{kPa} - 1.7 \, \text{kPa} = -0.27 \, \text{kPa} \]

Since the partial pressure of water vapor cannot be negative, it seems there might be an error in the given values or calculations. Please verify the input values and ensure they are accurate for further calculations.