Assume:
- Bottle A has a capacity of 100ml and contains 50ml of pg based nicotine
- Bottle B has a capacity of 55ml and contains 50ml of pg based nicotine
Bottle A will definitely oxidize faster than B, but could B reach the same level of oxidization? In other words, the amount of oxygen determines just the speed of oxidization or also the maximum level of it?
The max oxidation will be limited by the amount of oxygen dissolved in solution. This will be affected by the gas exchange rate which for a given solute/solvent system is mostly dependent on the surface area exposed and length of time. The rate is a little more complex, it is dependent on the amount of dissolved oxygen along with temperature and amount/intensity of light exposure, specifically UV light. The UV light is the big one since it acts as a catalyst by creating oxygen radicals. This is made easier/sped up by heat. So fr your scenario, if the bottles have the same diameter, are in the same environment, and are open top for the same length of time, the 100 ml will oxidize slightly slower. There are a lot of other smaller factors that could make a difference, but in general, work quickly, don't introduce more bubbles than necessary, protect from light, and maintain a stable storage environment to limit oxidation.
Why does bottle A react slower? I don't think it makes a difference since the area of the top layer is the same diameter. The nicotine is the same concentration. All other factors - pressure, temperature, etc are the same.
Also does light actually act as a catalyst here or does it degrade the nicotine on its own in a separate reaction? It would only speed up the reaction with oxygen by providing additional energy. Why would there be a limit to the amount of nicotine oxidized when there's an endless supply of UV light?
It is not a true catalyst as it is consumed in the process of creating the radicals bit otherwise it acts rather similarly to one since the "supply" is basically consistent (because more is always coming in, and at a pretty flat rate), so it's quite similar to a traditional chemical catalyst.
As far as does it have side reactions, probably it does, but the rate of the radical mechanism swamps out other competing mechanism that I'm aware of (but maybe OP knows otherwise)
The surface area of the liquid top layer will have an effect on how much oxygen can be dissolved when opening the bottle repeatedly, so... use a nice thin bottle!
Based on what OP wrote, Bottle A contains 50% nic by volume and bottle B has ~90.1% nic by volume. Bottle B has half the height of A. Assuming all other variables are the same, Bottle B would have ~twice the amount of dissolved oxygen and twice the amount of nic by volume so would, therefore, oxidize faster.
Regarding light as a catalyst, it depends on your exact definition of a catalyst but based on the definition that a catalyst is a species that directly or indirectly lowers the activation energy of the RXN in question it is certainly a catalyst.UV light would degrade nic on its own but IMO this would less important to the oxidation rate than the radial oxygen species produced by UV light + Dissolved oxygen. I've sort of tested this in my own recipes where I store my juice under inert atmosphere (Argon and/ Nitrogen) after mixing. For the same recipe of the same volume, in the same bottle type and, under the same light exposure conditions, the bottle stored under inert atmosphere oxidized about 2.5 times slower.
Thank you for your reply.
Maybe my question was a bit vague so I will try to give more assumptions, both bottles:
- Have the same diameter (different height) -> Same surface area
- Not exposed to UV light
- Not moving
- Were opened once for filling -> Limiting the amount of oxygen in each bottle
- Stored in the same temperature
I asked this question mainly to understand whether there is a theoretical limit for oxidization given a different and limited amount of oxygen. Will a 50/55 bottle (B) reach a maximum level of oxidization that is "smaller" than the 50/100 bottle (A)? Or both will oxidize to the same level given enough time?
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I am not sure I understand why bottle A will oxidize slower.
You need to agitate a mix. In ideal situations, this is in the bottle you plan to keep it in (as that's where you make it, on your scale) so when you shake the 50ml batch in the 55ml bottle, it ends up adding less oxygen into the mix than if you were to make a 30ml batch in the same bottle.
If these are bottles you're transferring nic base into, the nic poured into the taller bottle is exposed to air as it travels from your source bottle to the surface in the new bottle for longer than the nic poured into the shorter bottle. So there's more oxygen exposure. How much more exposure will depend on a number of factors.
How fast is the train going?
And when will they meet?