As an empiric observation, a glass container should hold water indefinitely. From a theoretical standpoint, a water molecule (2.75Å), should be able to pass through a glass pore (8-12Å)^[1]. A study using spectral analysis has shown the 12-19% of water exists as free water molecules^[2]. Our experiments demonstrated that an initial concentration gradient of free water molecules across a glass barrier along with hydrostatic pressure will force free water molecules through the pores in the glass jar until the concentration gradient is equal on both sides of the glass.

Methods

Latex gloves were worn when glass jars were handled. Jars were kept clean and wiped with alcohol to remove any skin oils or film that might block pores of the glass jars.

We placed a hygrometer (Roff C. Hagen (USA) Corp., Mansfield, MA) in a 500mL glass jar (Ball, elite wide mouth canning jar) with a tight-fitting plastic lid. Protocol 1. The 500 mL jar was inverted so the hygrometer reading could be viewed through the bottom of the jar when underwater. (Figure 1 A,B)

Figure 1: A. large acrylic container; a 500 mL jar with hygrometer on top. B. View of inverted sealed glass 500 mL jar with hygrometer under water

Velcro strips were used to fasten the air-filled jars to the bottom of a large acrylic container, Figure 1. All tests were conducted at room temperature between 68°- 72°. Distilled water (maintained at room temperature) was poured to fill a large acrylic container (Appx 4000 mL) with the inverted glass jar attached to the bottom. Hygrometer readings were recorded at 1-hour intervals. At the end of 4 hours the jars were removed from water and placed on a shelf in room air for 30 days.

In another series of experiments (n=8) the change in humidity was registered every 5 minutes for 2 hours (Figure 2).

Protocol 2. A similar set of experiments (n=6) were performed with both a hygrometer and an ion counter sealed in the jars under water and then placed outside in room air for 7 days.

Statistical analysis

Data are expressed as the mean + standard deviation (SD). Experiments (n=10) were performed to determine the reproducibility of results. We measured the average difference between 5 minute intervals as well as 5 minute interval means versus baseline (Figure 1). A student paired T-test was used to determine statistical differences. In the other series of experiments (n=8) we compared the change in the mean value in the first five minutes with the change in the mean value in the last 5 minutes. A p-value of <0.05 was considered significant.

Results

Protocol 1. In table 1 we measured the hour by hour changes in humidity compared to baseline values (n=10). In 2 experiments humidity reached 99% in 2 hours, whereas by hour 4 all jars showed 99% humidity.

Table 1: A spreadsheet showing the means and standard deviations in a series of experiments (n=10)

In another series of experiments (n=8) the percent change in humidity was registered every 5 minutes for 2 hours (Figure 2). The percent change of the first 5-minutes, 21% was significantly greater than the percent change in last 5-minute interval 1%, p<0.05.

Figure 2: A graphical presentation of the relationship between time (X-axis) and % humidity (Y-axis). The average 5-minute percent changes of humidity progressively decreased as humidity levels approached the maximum level, 99%. (See text for discussion).

After reaching 99% humidity the jars were removed from the water. Each jar was placed on a shelf to be observed for 30 days.

Protocol 2. In this series of experiments (n=6), Figure 3, the jars were fitted with both a hygrometer and ion counter and the humidity and ion count were followed daily when each jar was removed from the water, as in protocol 1, the jar was then placed on a shelf at room temperature. Humidity and ion levels were observed for 7 days.

Figure 3: A hygrometer and ion counter sealed in a 500mL jar underwater

Discussion

Major Findings

The present observations indicate that water passed through a glass barrier causing a progressive increase in humidity until it reached a maximum level of 99%. The rate of change in the humidity levels was not linear, the largest percent change in humidity was seen in the first 5 minutes and markedly slowed as it approached the maximum humidity levels (Hygrometers are 2-digit maximum reading 99%). These data show the free water molecule concentration gradient between the outside bulk water and the inside of the glass jar, was highest at the beginning of the experiment. The concentration gradient reached equilibrium as the free water molecule concentration reached maximum values in the sealed glass jar.

Mechanisms

Protocol 1. In this series of experiments, a bulk water source is separated from an air-filled container by a porous glass barrier. Free water molecules pass through the barrier by hydrostatic pressure and concentration gradient which allowed free water molecules to pass through the glass pores at a decreased rate over time, as indicated by the graph (Figure 2). When the jars were removed from the water, we observed the 99% humidity reading in the sealed jar remained constant for 30 days. To determine the mechanism for the lack of a reverse concentration gradient between inside the jar and the outside ambient environment, we performed another series of experiments. Protocol 2. Using the same procedure with the addition of an ion counter, not only did the humidity level remain constant for 7 days but there was a progressive increase in the ion concentration during that time period.

Figure 4: Graphic description of the relationship between ion counts and time in days.

In order to explain the findings of the maintained level of humidity and ion concentration in the jars over the long term we hypothesized that once the free water molecules were separated from bulk water their inherent kinetic energy produced free electrons stripped from the water molecules which initiated an ionization reaction. This reaction consisted of positive (H+) and negative ions (OH-) that became a self-sustaining plasma (the gaseous fourth form of water). Evidence in support of this hypothesis is the simultaneous existence of maximum humidity levels and high ion concentrations. Plasma is characterized as having properties of both a liquid and a gas. This presumptive plasma would represent another form of non-thermal plasma induced without any external energy input^[4]. The scientific, medical and commercial applications of this type of plasma can be readily studied since it can be acquired, stored and applied. In contrast, to non-thermal plasmas caused by high energy input which are short lived and difficult to separate their effects from the initiating energy source.

Limitations

It could be argued that water leakage into the jars when under water was the cause of the maintained high humidity observed in these experiments. After removal from the bulk water and the outside completely dried, we did observe water in some jars. This did not affect the production of plasma. The progressive increase in ionization was further evidence that the presumptive plasma was being formed in this environment. Also we noted that metal covers inhibited the observed changes. Plastic covers must be used.

Conclusion

We have described the construction of a novel humidity chamber based on the size difference between free water molecules (2.7Å) and the size of glass pores of the jars we used in these experiments (8-12Å). The segregation and confinement of these free water molecules is seen by a progressive increase in the humidity in the sealed jar under water until a maximum humidity of 99% was reached in 4 hours. When removed from bulk water the jar filled with free water molecules maintained the 99% level for 30 days. In another set of similar experiments an ion counter was added to the hygrometer in the sealed jars. Over a follow-up of 7 days, not only was the 99% humidity maintained, but there was a progressive increase the ion concentration indicative of a sustained ionization reaction.This reaction produced a novel form of non-thermal plasma without the application of external energy.

Conflict of Interest

None

References

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