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When a mixture of air and water vapour is cooled at constant pressure upto saturation temperature of water vapour, the temperature attained is known as:

When a mixture of air and water vapour is cooled at constant pressure upto saturation temperature of water vapour, the temperature attained is known as: Correct Answer Dew point temperature

Concept:

  • If unsaturated moist air is cooled at constant pressure, then the temperature at which the moisture in the air begins to condense is known as dew - point temperature (DPT) of air
    • If the dew - point temperature is close to the dry air temperature - the relative humidity is high
    • If the dew point is well below the dry air temperature - the relative humidity is low

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  • Dry Bulb Temperature: Actual temperature of gas or mixture of gases.
  • Wet-bulb temperature: Temperature obtained by an accurate thermometer having a wick moistened with distilled water.
  • Dew point temperature: Temperature at which the liquid droplets just appear when the moist air is cooled continuously.
  • Sensible heating: Moisture content of air remains constant so specific humidity is constant, temperature increases as it flows over a heating coil.
  • Sensible cooling: Moisture content of air remains constant so specific humidity is constant, but its temperature decreases as it flows over a cooling coil.

Related Questions

Consider the following statements and choose the correct answer:
1. A direct proportionality exists between vapour pressure and the concentration of water vapour in the atmosphere
2. Relative humidity is an expression of the ratio of the actual vapour pressure of the atmosphere when saturated at the same temperature
3. A rise or fall in temperature with no change in vapour pressure will cause a drop or rise, respectively, in relative humidity
4. A rise or fall in vapour pressure with no change in temperature will be accompanied by a rise or fall, respectively, in relative humidity
An air-water vapour mixture has a dry bulb temperature of 60°C and a dew point temperature of 40°C. The total pressure is 101.3 kPa and the vapour pressure of water at 40°C and 60°C are 7.30 kPa and 19.91 kPa respectively.The humidity of air sample expressed as kg of water vapour/kg of dry air is
Relative humidity is given by (where pv = Partial pressure of water vapour, pb = Barometric pressure, ps = Pressure of saturated air, pd = Pressure at dry bulb temperature, pw = Saturation pressure corresponding to wet bulb temperature, and μ = Degree of saturation)
Relative humidity is given by (where pv = Partial pressure of water vapour, pb = Barometric pressure, ps = Pressure of saturated air, pd = Pressure at dry bulb temperature, pw = Saturation pressure corresponding to wet bulb temperature and $$\mu $$ = Degree of saturation)
Statement (I): Piston temperature profiles near full load are flattened in case of liquid cooled engines whereas for air cooled engines temperature profiles are steeper. Statement (II): The piston temperature profiles are different in nature for liquid cooled and air cooled engines because of the different values of heat capacities.
Consider the following statements: 1. The relative humidity of air does not change with temperature as long as specific humidity remains constant. 2. Dew-point temperature is the temperature at which condensation begins when air is cooled at constant volume. 3. Saturated air passing over a water surface does not cause change of air temperature. 4. For saturated air, dry-bulb, wet-bulb and dew-point temperatures are identical. Which of the above statements are correct?
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Saturated solution of benzene in water is in equilibrium with a mixture of air and vapours of benzene and water at room temperature and pressure. Mole fraction of benzene in liquid is xB and the vapour pressures of benzene and water at these conditions are PvB and Pvw respectively. The partial pressure of benzene in air-vapour mixture is
The following question has three statements. Study the question and the statements and decide which of the statement(s) is necessary to answer the question. 6 litres of mixture A and 4 litres of mixture B are mixed to form a new mixture C. Find the amount of water in the new mixture. I) The new mixture had alcohol and water in the ratio 7 ∶ 5. II) Mixture A had alcohol and water in the ratio 5 ∶ 4. III) Mixture B had alcohol and water in the ratio 5 ∶ 3.
Jar A comprises a mixture of milk and water in the ratio of 3 : 2 respectively. Another mixture of milk and water is added to jar A and the ratio of milk and water in the resultant mixture changes. What was the initial quantity of mixture present in Jar A? I. The ratio of milk and water in the mixture that was added to Jar A was 2 : 1 respectively. II. The ratio of the new quantities of milk and water in Jar A was 8 : 5 respectively. The quantity of water in the mixture added to jar A was 6 litre.