High School Photo Winner's Showcase

School: Sleepy Hollow High School

Teacher: Leila Madani

This picture is of some snow in a snow drift at the entrance of Sleepy Hollow High School. The formation of the snow’s shape in this image is due to heat transfer and the molecular shape of the water. The snow was blown into the corner of the building on a cold, snowy day. However, during the day, the buildings are heated. Since heat transfers from hot to cold and the walls are diathermal (meaning heat can flow through it), the outside brick wall is slightly hotter than the surrounding air. This could have allowed for the snow to begin melting where it was in contact with the wall. Then, the slightly liquid snow flowed into the crevices of the brick and took the wall’s shape. During the night, when the air was colder and the temperature of the building lower (since most buildings reduce their heater settings overnight), the snow refroze against the wall, now molded into the shape of the bricks. The most likely reason the snow stayed together when it peeled off is due the properties that arise from the shape of the H2O molecule. It is a bent, polar molecule and it has a tendency to stick to and bind with other water molecules, in a process known as Hydrogen Bonding. Because of this, the water molecules interlock and resist movement. This is how the ice was able to stay together while teetering away from the edge of the wall.