If you are spending the holidays far from the city and the coast, you may be lucky enough to live an idyllic and white christmas print. The snow completely changes the orography of the landscape, hiding the paths and dressing the trees with bridal veils. The silence that accompanies it is almost mystical.
On the contrary, if you have spent your childhood far from the snow, surely at some point you sacrificed your little hands to play games. do balls with the ice that formed in the freezer drawers. Although this was before “no frost” technology was invented, of course.
But Are snow and snow the same? ice What forms in the refrigerator? Well, although we could not distinguish them due to their composition, the difference is found in the training conditions.
Water is the great protagonist of this planet. And one of the reasons is that we can easily find it in the three fundamental states of matter: solid, liquid and gas.
The following experiment demonstrates the versatility of water and is easily replicable in our homes. In addition, it implies a very low risk, so the little ones can accompany us in its execution: if we cool liquid water to 0eitherC in the freezer, we will get an ice cube. If we heat it up to 100eitherC in a pot, it will become water vapor.
Perhaps the result is not very spectacular, but it is adequate to introduce the following question: Why doesn’t the ice that has formed look like snow? Or better, if we have cooled it in the freezer, Why doesn’t it look like frost?
This experiment shows us, neither more nor less, that The conditions in which the water solidifies will be responsible for the final shape. Therefore, we can now deduce that they will not be the same for snowflakes as for frost.
In the case of the latter, Its formation comes from the direct solidification of water vapor. A process known as sublimation and that we can also observe on the leaves of the bushes on cold winter mornings. For frost to form, the temperature must be between -3°C and 0°C and the humidity quite high..
On the contrary, Snow is formed from the agglomeration of small ice crystals solidified in clouds.. And no, although it may surprise you, clouds are not formed by water vapor, but are large clusters of droplets suspended in the atmosphere.
Water solidifies around small particles of impurities, serving as a nucleus for the agglutination of ice crystals that, as their weight increases, fall in the form of snow.. But in this case the process is more complex and the structure of the snowflake will depend on factors such as temperature, pressure, humidity… Or have you ever seen two identical flakes?
When we think of a snowflake, that fractal structure with six main arms that branch out until we obtain complex stars usually comes to mind. However, it is not the only form that these can take. It will depend in part on the temperature and humidity that we find within the cloud in which they form.
This perfect structure is not the most typical. It happens when Ice crystals form directly from water vapor and subsequently agglutinate, arranging themselves in a fractal manner around a hexagonal crystal.. The optimal conditions range between -10 and -20eitherC and the humidity must be high.
Between -5 and -10eitherC, the most typical structure is that of a needle, which reminds us of what we find when eating a popsicle ice cream in summer. Besides, if temperatures are around -20eitherC and the humidity is not very high, we will probably observe small hexagonal crystals, but without branches.
One of the main researchers of this phenomenon was the astronomer Johann Kepler, whoIn 1611 he described the hexagonal growth of snowflakes. Besides, In 1885, Wilson Alwyn Bentley took the first photo of one of these structures.. Thanks to his extensive work, which has more than 5,000 imagesmanaged to do one of the first classifications of its growth according to temperature and humidity.
That no two snowflakes are alike is relative.. Recently, physicist Kenneth G. Libbrecht managed to synthesize two identical snowflakes in his laboratorycontrolling the different parameters involved in its growth.
However, some of us still think that The beauty of these lies in the randomness that nature itself has destined for them..
DON’T BE KNOWN:
- Sleet appears when raindrops freeze completely or partially as they pass through a cold stratum. That is why it does not give rise to well-formed snowflakes.