The EEC Logo

EXTRA INFORMATION (BEYOND RSC COMPETITION) FOR
"WHY DOES HOT WATER FREEZE FASTER THAN COLD WATER?"

The note from Hermes, closing the final submission deadline for the competition.

#
17 August - updated with more experiments & results - and a working prototype of a device to treat (without heating) cold water, making it freeze faster than untreated cold water and in fact faster than boiling hot water.

Omission from Experiment 3 (Piezo)
Apologies folks, I did not upload all the data files for this experiment on the main page , so here's the complete set.

Temperature profile of Hot Start v Cold Start freezing water, with and without help from the piezo transducers

piezo_cold_start_control.txt = temperature profile data for freezing water from the cold tap with no help from the piezo transducers.
piezo_cold_start_running.txt = temperature profile data for freezing water from the cold tap with the piezo transducers running.
piezo_hot_start_control.txt = temperature profile data for freezing water from the hot tap with no help from the piezo transducers.
piezo_hot_start_running.txt = temperature profile data for freezing water from the hot tap with the piezo transducers running.
piezo_graph.gle = the GLE script to graph the above data sets.


New Experiments
I designed some new experiments to investigate some of the issues raised during the work for the RSC competition.
Here are the experiments....


#
New inert (stainless steel) electrodes

Details of the new inert (stainless steel) electrodes.

#
The new inert (stainless steel) electrodes in use

The new HIVE inert (stainless steel) electrodes in action.

#
Circuit details for measuring HIVE electrode current while running

Circuit details for measuring HIVE electrode current while running.

#
Cleaning the containers before the next set of experiments

Some of my (not published) previous experiments did not perform very well.
The assumption is that there was contamination in or on some of the equipment used.
Before the next set of experiments, I washed all the containers and other equipment in contact with
the water samples in a weak solution of domestic washing up liquid,
rinsed them well in normal cold tap water and left them to dry as shown above.

If there still is contamination present (maybe soap residue), it should effect all the experiments to the same level.
Once a container has been used in an experiment, it will not be used in another experiment to avoid cross contamination.

Equipment 8 - Freezing De Ionised Water
Objective:
Use De Ionised Water rather than tap water and compare the results for:
(1) Freezing De Ionised Water from cold.
(2) Freezing De Ionised Water from Boiling.
(3) Freezing De Ionised Water from cold, after treating with the HIVE , using inert electrodes for 30 minutes.

Predictions:
I would expect to see the untreated cold water sample take longer to freeze, the boiling water sample freeze faster
than the untreated cold water and the water treated with the HIVE freeze in the shortest time.


Complete details of the other equipment used in this experiment can be found here .

#
Details of the de ionised water used for the experiment

Details of the De Ionised water used for the experiment.
Note: it's not sourced from a scientific supplier, but the type of water used to top-up automobile & truck lead acid batteries.

#
HIVE electrode current profile when using de ionised water

HIVE electrode current profile when using de ionised water.

#
De ionised water freezing from cold, boiling and treated with the HIVE

De ionised water freezing from cold, boiling and treated with the HIVE .
Click on the graph or here to see the full graph.

di_sample_cold_start.txt = the raw temperature profile data for freezing cold de ionised water.
di_sample_boiling_start.txt = the raw temperature profile data for freezing boiling de ionised water.
di_sample_ion_drive_cold_start.txt = the raw temperature profile data for freezing cold de ionised water after 30 minutes of HIVE treatment.
di_sample_graph.gle = the GLE script to graph the above data sets.


Experiment 8 Conclusion
Observations:
The Mpemba effect was not seen when using de ionised water - i.e. boiling water took longer to freeze than cold water.

Issues raised by the observations:
The Mpemba effect may rely on dissolved minerals and / or gasses in the water sample.


Equipment 9 - Freezing Bottled Mineral Water
Objective:
Use Bottled Still Mineral Water rather than tap water or De Ionised Water and compare the results for:
(1) Freezing Bottled Mineral Water from cold.
(2) Freezing Bottled Mineral Water from Boiling.
(3) Freezing Bottled Mineral Water from cold, after treating with the HIVE , using inert electrodes for 30 minutes.

Predictions:
I would expect to see the untreated cold water sample take longer to freeze, the boiling water sample freeze faster
than the untreated cold water and the water treated with the HIVE freeze in the shortest time.


Complete details of the other equipment used in this experiment can be found here .

#
Details of the mineral water used for the experiment

Details of the mineral water used for the experiment.
This Buxton mineral water was chosen because it's got a list of the minerals & their concentrations on the label.
Similar mineral waters & details of their mineral concentrations are available here .

#
HIVE electrode current profile when using buxton mineral water

HIVE electrode current profile when using Buxton Mineral Water.

#
Buxton Mineral water freezing from cold, boiling and treated with the HIVE

Buxton Mineral Water freezing from cold, boiling and treated with the HIVE.
Click on the graph or here to see the full graph.

buxton_sample_cold_start.txt = the raw temperature profile data for freezing cold Buxton Mineral Water.
buxton_sample_boiling_start.txt = the raw temperature profile data for freezing boiling Buxton Mineral Water.
di_sample_ion_drive_cold_start.txt = the raw temperature profile data for freezing cold Buxton Spring Water after 45 minutes of HIVE treatment.
buxton_sample_graph.gle = the GLE script to graph the above data sets.


Experiment 9 Conclusion
Observations:
The Mpemba effect is still not visible, but the time to freeze hot water is faster than De ionised water.

Issues raised by the observations:
Maybe the concentration of minerals in the sample affects the time for hot water to freeze.
Our tap water is in a hard water area (>200mg/l Calcium), whereas the Buxton sample has 55mg/l Calcium and
De Ionised water has virtually no dissolved Calcium.


 Buxton Mineral Water v De Ionised Water

Buxton Mineral Water v Di Ionised Water.
buxton_v_di_water_graph.gle = the GLE script to graph the above data sets.