H2 Oh!
“Mom, Mom you gotta see this!!! You gotta! Come with me, hurry, hurry, up! Come right now!!!”
My four-year-old son's insistence hit my ear at around fifty decibels and I winced even as I laughed and followed Seric out the door for yet another look at something he had recently discovered.
A large sheet of ice stood on end propped against a step stool, facing the early winter's sun. His eight-year-old sister, JudyLucy, was carefully trying to redistribute the weight of the ice to balance it so that the sun hit the glittering surface as evenly as possible.
“Look, Mom,” she said reverently as she knelt before the standing sheet of ice. Daddio had just broken the ice on the pool, which now served as a cattle tank for our two cows. He had lifted a sheet of two-inch-thick ice out of the pool for the kids to examine.
“Look at the patterns!” JudyLucy exclaimed, admiring the lacy design in the sheet of ice.
“It's already melting,” Sarah (7) observed. “You can see the sun right… there,” she said, pointing to the sun's reflection on the icy mirror. “It's melting most right where the sun is shining.”
“How long do you think it will take it to melt?” David (10) asked.
“A couple hours.” Daddio replied, fishing a few smaller pieces of ice out of the tank for Seric (4) and America (3) to play with. Seric hurled a chunk at the driveway and shouted in glee when it exploded in a thousand shining pieces. America was tasting her piece.
“Don't lick it,” JudyLucy instructed. “It's not clean.”
“The pool is fuller than it was last night,” David commented. “Did it rain too?”
“No,” said Daddio, “the ice expanded.”
“Is ice lighter or heavier than water?” David asked.
I laughed, loving the process of learning and looking forward to hearing Daddio's explanation… again. He'd answered that question before and this time prefaced his answer with questions, prompting his students to think a little harder before he answered.
“What do you think?” he asked.
“That ice is lighter,” said David, “because it has air in it.”
“It's the same,” said JudyLucy, “because… because… I don't know why.”
Daddio smiled but was quiet, waiting for more input.
“Yeah,” said David, “maybe it IS the same, but it's bigger because it has air in it.”
“How does it get air in it?” Sarah asked, looking closely at a chunk in her hand. “Oh, yeah! I can see tiny bubbles in it! Look, Mom!”
I looked at the ice she held and saw the air bubbles in the chunk of ice seemingly without pattern like the lacy exterior. Daddio finally spoke, holding up a chunk of ice.
“This ice weighs the same as it did when it was liquid, except for maybe a minuscule amount which evaporated between liquid and solid state. The air in it does not make it lighter, and it is not the air that causes it to expand.”
“What makes it expand then?” David asked. Daddio dropped the ice and put his hands out, holding up his index and middle fingers in the shape of a V.
“Water molecules are charged magnetically,” he said, pointing with one hand at the base of a V, “this end is negative, and the open end is positive. When they are in above-freezing temperatures they are relaxed and move against each other like this,” he relaxed his hands and let the two Vs move against each other. “When the temperature drops the magnetic particles begin to slow down until they stop moving and stand rigid against each other in a magnetic lattice, which is bigger than when they are relaxed and moving close together.”
“But what about the air bubbles?” I asked.
“When the magnetic particles of water begin to slow down and get rigid, impurities in the water get in the way. Those impurities are pushed aside and together. The pushed-together impurities seem to form pockets with (previously) dissolved air in the water, er, ice.
“I am not sure exactly how it works, but that is what others believe they have seen.”
I picked up a chunk of ice and ran my thumb over a surface bubble. Sure enough, it was gritty and dirty feeling. I saw the older kids doing the same.
The large sheet of ice was melting as we talked. JudyLucy checked the outside temperature. It was 43 degrees in the sun and rising.
We went inside for breakfast and an hour later went out to find that the sheet of ice had melted in such a way that a beautiful icy skeleton was all that remained. It was fragile, but still intact and standing erect. Water ran down the decline of concrete driveway in front of the ice. JudyLucy put out a cautious finger and lightly touched the translucent surface. Suddenly the structure collapsed, resulting in a surprisingly small pile of ice.
Seric spoke first, “Can we do it again tomorrow?”
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