I plan to run a humidifier with lights on(to achieve VPD sweet spot).. then when the lights go off, i plan to have a dehumidifier kick in to counter the high humidity. Any opinions? For those who add humidity for VPD what do you do about the high humidity when lights turn off?
Xin Wang Title To measure the enthalpy of vaporization and the boiling point of diethyl ether by cooling the ether down and continuously recording a series of different temperature readings and the.
TL:DR What options are there to mimic the colour output of low pressure sodium vapour bulbs to fill a room with light?
A few years ago I saw Olafur Eliasson’s 'Room for one colour' at the National Gallery in the UK in which a bunch of low-pressure sodium vapour lights flood a large white room. This (as I’m sure you all know) outputs a narrow band of yellow light which makes everything look monochromatic and the whole experience was so interesting that I’ve been wanting to recreate it at home.
The obvious answer is to setup a low sodium lamp but for the sake of simplicity I’ve been trying to find another solution which brings me here to see if anyone might have any insight.
My first thought was to use some sort of optical filter with a conventional bulb behind it to filter out all but the required wavelengths. However a lot of what I can find are physically very small and fairly expensive industrial imaging/laser filters.
The other option I’ve seen is narrow band light bulbs designed for medical or plant growing but it’s hard to find any hard data on the exact light output of these things and I suspect they may be a bit too broad and might not create the desired effect.
So I’m mostly spit balling at the moment but curious if anyone with more knowledge could perhaps shed a bit of light ;)
This problem says Benzenes vapour pressure at 25 celcius is 0.131 atm but benzenes boiling point is 80 celcius... how can there be a vapour pressure if there is no boiling?
I am not a botanist and reading about VPD. I am trying to find a reference for VPD for cacti but all I find is general tables for plants at different maturities -aimed mostly at growing marijuana or other plants for consumption, which I am not interested in.
From my basic understanding, I would expect that VPD requirements would be a genetic adaptation (ie. arid plants would have different requirements to tropicals).
However, I don't know the fundamental stomata mechanism like you all would and unfamiliar if they behave similarly across all plant species or not.
Thank you in advance! Also if you have any references for various plants, it would be appreciated! I did a few Google scholar searches and came up empty handed, perhaps because I am not using the right search keywords.
A new post is up on my blog. I do these things when I feel it will add to someone's knowledge and when, frankly, I feel the need to reinforce my own understanding. And there's no better way to do that than trying to explain it.
Join me on the journey if you like. The more you know, the more you grow.
So vapour pressure is the pressure caused by the vapours of a liquid escaping into the atmosphere. In the closed system, this reaches a liquid-vapour equilibrium. In an open environment, this vapour pressure is at the interface between liquid and air.
The atmospheric pressure doesn't necessarily have a relationship with vapour pressure but will push down on the liquid, preventing it from vapourising, unless the vapour pressure of the liquid becomes equal or exceeds this pressure.
This is my understanding of vapour pressure. Can someone confirm if that is true?
Now my real question is, to calculate vapour pressure we have Antoine, Dalton, Raoult's & Henry's law and the Clausius-Clapeyron Equation. Though, all these equations are said to be used for ideal solutions, where the intra-molecular forces don't interact with each other. Obviously life plays out differently, so how do we calculate the vapour pressure in a real-life industrial setting? Do we still use these equations anyway? For pure substances I guess you can still just use Antoine, but what about binary and tertiary mixtures?
Thanks
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I was reading about azeotropes on wiki
I came across the following:
>When the deviation is great enough to cause a maximum or minimum in the vapor pressure versus composition function, it is a mathematical consequence that at that point, the vapor will have the same composition as the liquid, resulting in an azeotrope.
I don't get how it is a mathematical consequence of the vapour pressure attaining a max/min.
It'd be really nice if someone could help me out with this.
When you have oxygen in the air, the partial pressure of it is: 160mmHg for 0.21% of O2
When you have oxygen in the trachea, the partial pressure of it is 150mmHg for the same 0.21%, because you add water vapour.
I can't figure why partial pressure of oxygen decreases when you add water vapour. I explain: Image one box with 1 liter of volume and oxygen making 160mmHg of pression in that box. If u put water vapour in that 1L box, thinking with logic the oxygen partial pressure will increase, not decrease to 150mmHg (because you are adding things to a finite space). I just can't figure it out why this decrease of 160 to 150 happens.
I can't understands why that happens. I see the numbers and calculations (PO2intrachea = (760-47)0.21), but can't explain why. The partial pressure of a gas shouldn't be equal in the same conditions of temperature and volume? You have the same values of mols of oxygen, but different results of partial pressure???
I have relative humidity (%), temperature (K), and Absolute Air pressure (Pa). I should be able to obtain partial pressure of water vapour.
Thanks in advance.
Xin Wang Title To measure the enthalpy of vaporization and the boiling point of diethyl ether by cooling the ether down and continuously recording a series of different temperature readings and the.
Xin Wang Title To measure the enthalpy of vaporization and the boiling point of diethyl ether by cooling the ether down and continuously recording a series of different temperature readings and the.
