Estimate Mass H2O Vapor in 1 m^3 Air at +20°C

  • Thread starter Thread starter Orbital
  • Start date Start date
  • Tags Tags
    Absolute Humidity
AI Thread Summary
To estimate the mass of water vapor in 1 m³ of saturated air at 20°C, the saturation pressure for water vapor at this temperature is essential. The ideal gas law can be applied using the formula m_{H2O} = P_{sat, H2O} / (R_{H2O}T), but attention to units is crucial for accuracy. The discussion highlights a potential issue with the phrasing of the problem, suggesting it may not be physically correct. Clarification on the problem's wording is necessary to ensure proper understanding and application of the concepts. Accurate calculations depend on both the correct use of the ideal gas law and the precise definition of saturation in this context.
Orbital
Messages
12
Reaction score
0

Homework Statement


Estimate the mass of water vapor that is contained in 1 m^3 of saturated air at a temperature of plus 20 degrees Celsius

2. The attempt at a solution
I looked up the saturation pressure for water vapor at the given temperature. Can I just use the ideal gas-law for the mass? i.e. is the solution as simple as
m_{H_2O} = \frac{P_{sat, H_2O}}{R_{H_2O}T}
or do I have to make another approach?
 
Physics news on Phys.org
yes this looks right, but -as usual- be careful with the units
 
Last edited:
Can you tell me why the phrasing of the problem is physically incorrect?
 

Thread 'Struggling to understand the concept of this question (ice cube in water optics question)'

TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
View full post »
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
View full post »

Similar threads

Calculate the amount of water vapor
Replies
3
Views
2K
Relative Humidity Changes in a Closed Room
Replies
1
Views
2K
A five-liter pot is filled with 2 l of liquid water and 3 l of dry air....
Replies
24
Views
3K
Dew point and absolute humidity
Replies
3
Views
2K
I Is equilibrium vapor pressure different in vacuum and in air?
Replies
2
Views
2K
Thermodynamics - Saturated Vapor Quality Question
Replies
3
Views
3K
Adiabatic Expansion of Pressurized Air in a Piston-Cylinder Setup
Replies
8
Views
2K
Modeling a kongming lantern (sky lantern)
Replies
6
Views
2K
Volume occupied a single molecule of water.
Replies
9
Views
3K
Thermodynamics: Air and Steam Mixtures
Replies
4
Views
4K

Hot Threads

Recent Insights

Back
Top