Measuring dissolved H2 in water produced using "open glass" H2 tablets:
Some H2 tablet manufacturers & retailers recommend placing their tablets into an "open-glass" rather than a sealed container. These tablets produce H2 water characterized by a dense "milky fog" (see picture) that does not dissipate quickly, often lingering in the container for many minutes. When using H2Blue to measure hydrogen-rich water produced by these types of magnesium tablets, a measurement taken from a sample (e.g. 500 mL) may require over 100 drops of the ethanol-based H2Blue before reaching the titration endpoint. This suggests a dissolved H2 level of 7.5 to 10 mg/L (at 0.1 mg/L per drop). This may seem impossible without accompanying pressure. However, due to the apparent micro and nanobubbles formed, there exists an internal pressure in the individual gas bubbles that can reach very high levels according to the Laplace equation. The concentration of dissolved H2 gas is proportional to the gas pressure within the bubble according to Henry’s Law. Small bubbles release gas into the solution, and large bubbles uptake gas from the solution and grow. This process is called "Ostwald ripening".
Under these conditions, during which the, water becomes saturated with H2, much of the remaining gas is in a "quasi-dissolved" state. As drops of H2Blue are added to the sample, the dissolved H2 gas is consumed by the reaction, making it possible for more H2 to be released from the bubbles and dissolve into solution, where it will then react with more H2Blue (notice also that, under the right conditions, gas being produced by the magnesium may dissolve directly into the water without becoming "quasi-dissolved" first). This cycle of consumption and dissolving will continue until all of the available dissolved & "quasi-dissolved" H2 gas in the sample has been consumed, and all of the magnesium has reacted (see diagram).
What can the total # of drops added tell us about the H2 water being measured?
While counting the number of drops added does not tell us what the "peak" dissolved level of H2 is, we can still use the total number of drops added to calculate the approximate amount of H2 that will be ingested, which will include both the dissolved and the “quasi-dissolved” H2. Because we can also calculate these same values in any other H2 water, they can be used as an important tool for comparing ingested levels of H2 across many different H2 water technologies. There are some technologies that produce very cloudy/foggy water, but give very low readings with the H2Blue. This simply means that the total amount of H2 in this water is very low since there is a direct relationship between dissolved and undissolved H2 according to Henry’s law. That is, H2 gas is simultaneously dissolving into the water, and forming larger bubbles (coalescing) and escaping into the atmosphere. Indeed, if all the H2 gas produced from these types of tablets was dissolved in solution, then the readings with H2Blue would likely be even higher since it would measure the gas before it escaped into the atmosphere.
Comparing the performance characteristics of the H2Blue eco formula and ethanol-based H2Blue:
The ethanol and eco formulations of H2Blue perform identically for most types of hydrogen-infused water. However, when comparing the performance of the new H2Blue eco formula to the ethanol formula for this specific type of H2 water, fewer drops of the reagent need to be added before reaching the endpoint (perhaps as much as 50% fewer than the ethanol). This may be due to differences in the specific gravity, hydrophobicity, surface tension, ionic strength, etc. between the carrier solvents of the two formulations. These differences may affect the zeta-potential, bubble stability, rate and propensity for bubble coalescence, etc. The ethanol formula does not appear to have a negative impact on the equilibrium between the "quasi-dissolved" and dissolved H2. The eco formula, however, tends to destabilize these bubbles, which increases their growth and coalescence. Therefore, much of the gas can escape into the atmosphere and avoid detection, resulting in a lower measured H2 level. While the eco formula can still be used as a reliable "indicator" of the relatively high levels of H2 gas in this particular type of water, if more accuracy is required, we recommend that you consider using the ethanol-based H2Blue.
Please Contact Us for more information about purchasing the ethanol-based version of H2Blue (special-order only, may not be available to resellers).
Because ethanol-based products are classified as "dangerous goods" by USDOT (49CFR), international IATA (DGR), and other regulatory agencies worldwide (class III flammable), they are not permitted to be shipped via the US domestic/international postal service (USPS) without special, written permission. Other carriers (UPS/Fedex/DHL) permit shipping of dangerous goods only after completing hazmat certification training and complying with specific packaging, labeling, handling, and documentation requirements (very large fines can be imposed, even for first-time violators). Therefore, the H2Blue eco formula is the best choice for consumers in most circumstances.