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Why Is Ice Slippery? Earth

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Why Is Ice Slippery? Earth 24 SectionSection AA MARCH 2009 The Woodside News THE BIBLE AND SCIENCE BY WILLIAM T. PELLETIER, PH.D [WOODSIDE NEWS COLUMNIST] Why Is Ice Slippery? earth. Except for Ice Ih and Ice Ic, the other forms of ice o you toss and turn and are denser than water and Dlose sleep trying to fig- sink. ure out why ice is slippery? Water is essential for life. If you can explain precise- It slakes thirst and is the best ly why ice is slippery, you and cheapest solvent and could win a Nobel Prize. cleanser. Yet the water mole- PHOTO BY ALEXMUSE/FLICKR.COM Scientists do not know the cule (H O) is one of the WILLIAM T. PELLETIER 2 answer. Arguments over dif- PH.D. simplest molecules. Man is ferent hypotheses persist. still struggling to understand Physicists now say the com- the secrets of this “simple” mon explanation in textbooks is wrong. molecule. Scientists study the different On the other hand, why does ice forms of ice hoping to better under- grip so tenaciously? Removing ice stand how the water molecule works from smooth windshields or from con- in plants and animals. crete sidewalks can be very difficult. The adhesiveness of ice is due to WHY DOES SALT MELT ICE? strong molecular bonds ice forms with When salt water freezes, the salt many substances, including glass, con- moves to the surface. Icebergs are free crete, and skin. of salt below the surface, despite float- Why does ice grip so tenaciously? ing in salty oceans. TYPES OF ICE The ice that you slip on even accurately predict the weather more in the parking lot and Want to win a Nobel prize in than a few hours in advance, much less use to chill drinks is just control or even significantly affect it. one of at least 20 differ- The Almighty alone controls the weath- ent molecular forms of physics? Just answer one er for His own sovereign purposes. ice that have been dis- Yahweh uses weather to get man’s covered. Common ice is simple question! attention and to speak to him (2 Chron called Ice Ih because 7:13,14; Amos 4:7,8). Sometimes the water molecules are weather and morality are connected as arranged in a hexagonal pattern. Salt is sprinkled over winter roads Common table salt isn’t the only salt vividly demonstrated by Noah’s Flood Another form is Ice Ic, found high in because it lowers the freezing point of that can be used. Other salts are more (Genesis 6). The same lesson in reverse the atmosphere having cubic crystals. water or the melting point of ice and effective (but more expensive) in lower- (drought instead of flood) was delivered Other forms of ice are identified reduces the slippery ice hazard. ing the melting point of ice. For exam- to Israel’s King Ahab 1650 years later (1 as Ice II, Ice III,…, Ice XV. These When dissolved in water, salt ple, calcium chloride lowers it to –20OF. Kings 16:30-18:46). Noah’s Flood and forms occur only at extreme tempera- (NaCl) splits into sodium and chlorine Ahab’s Drought were weather-delivered tures and pressures that you and I are ions which form weak chemical bonds ICE IN THE BIBLE divine moral judgments. unlikely to encounter (you won’t find with water molecules. This solution Where did ice and water come from? Extreme winter weather seals the them in the parking lot or ice stays liquid at much lower tempera- The Almighty created water on Day hand of every man (prevents ordinary machines). Ice XII was only discov- tures than pure water because the sodi- One in abundance (Genesis 1:1-2). business and work) for the purpose ered a dozen years ago. um and chlorine ions “get in the way” Weather extremes are of great that all men may know His work ( Job Common ice (Ice Ih) floats because and impede crystallization into ice. human interest. One of Yahweh’s 37:5-7). Remember this verse when it’s less dense than water. This is unusu- The more salt that is dissolved in “unanswerable” questions to Job was snow cancellations occur, and instead al. Most solids are more dense than water, the more it lowers the freezing where did ice come from ( Job 38:29). of bemoaning the ice, praise Yahweh their liquid forms. If ice were denser point (impedes crystallization) until Cold, ice, and snow all come from the for His glory, majesty and power. than water it would sink to the bottom the water is saturated with salt. Almighty ( Job 37:5-13; 38:22,23; of water bodies killing most marine life Under lab conditions, this minimum Psalm 147:15-17). E-mail Dr. Pelletier at over the winter. Being at the bottom, temperature is –6OF. On the street, Sometimes weather changes by [email protected]. ice would not melt over the summers. salt can melt ice only down to about dozens of degrees in a single day. Can Read the Bible-Science Guy Blog at In a few years all water bodies would be 15OF. There is no point in salting man cause this? Can man freeze a lake http://woodsidebible.org/category/ frozen solid, and life would die out on roads below 15OF. as Yahweh can? ( Job 38:30) Man cannot blogs/bible-science-guy/ ©20 0 9 William T. Pelletier Ice cream in a bag BY WILLIAM T. PELLETIER, PH.D. into the gallon bag and seal. WOODSIDE NEWS WRITER Shake the gallon bag gently for 10-15 minutes as the “ice cream urge” ever until the ice cream is firm. Hhit when the freezer was Heat energy from the empty and you couldn’t bring mix melts the ice, thereby yourself to drive to the store? cooling the cream mix. The Here’s a fun solution – make your cream mix freezes (at a lower own double scoop in 15 minutes! temperature than water) PHOTO BY NINJAPOODLES/FLICKR.COM Put 1/4 cup sugar, 1/2 cup because the ice-salt mixture milk, 1/2 cup whipping cream, has a lower freezing/melting and 1/4 teaspoon vanilla in a point than pure ice. quart zip-lock bag. Add desired flavorings E-mail Dr. Pelletier at Bible (strawberries, chocolate chips, [email protected]. etc). Double-bag and seal. Read the Bible-Science Guy Blog Fill a gallon zip-lock bag 1/3 at http://woodsidebible.org/ full of ice. Add a cup of salt. category/blogs/bible-science-guy/ Place the sealed quart bag ©20 0 9 William T. Pelletier Making ice cream in a zip-lock bag.
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