Why do ice float on water?
Quote of the day from India's LTC Rajyavardhan Rathore, silver medalist of Trap Shooting in the 2004 Athens Olympic...
"Its the not your condition that decides your future, its your decision that decides your future."
Now back to the topic of the day. Everyone observe that ice cube floats on water but wonder why? Well most of us do know that water, unlike other liquid, expands instead of shrink when it solidifies. This is contradictory according to conventional science we studied in the past. As we all ex-secondary school-ers learn, the molecules of gas is further apart than in liquid and liquid are slightly apart than in solid. This means a 1kg of gas will have a larger volume than 1 kg of liquid which will have slightly more volume than 1 kg of solid. Ok, this maybe getting a bit confusing but take this general rules as starter -- Volume: Gas>Liquid>Solid.
I came across this interesting facts about liquid and solid while revising for the coming Monday test, almost all materials are more dense in solid state than in liquid state. That means when molten aluminium, copper or steel solidifies in a casting, it actually shrinks! Which means if you were to pour 1 litres of molten steel into a cylindrical casting, after solidification, it might end up occupying 0.9 litres. The same old law applied, "mass cannot be created or destroyed" thus in this case 1 litre (volume) of molten steel will have the same mass as 0.9 litres of solid steel and the only difference will be the density. If we were able to drop this solid steel into molten steel, it will be observed that the solid steel will sink.
However water undergoes an interesting process, instead of shrinking when it freezes (solidify), it actually expands! And due to this expansion or increase in volume, ice (solid water) had less density than water (liquid), thus ice floats. Ta da!!!! For those interested in the figures, water volume expands 8.3% when it freezes. That explains why your coca-cola and pepsi cans become bloated when you freeze it in the chiller. That also explains why soft drink maker will never fill up the entire can or else the absents minded who wanted a quick chill of their soft drink might end up with a big freezer mess from exploding cans (over expansion).
Now here is a little IQ question involving water. You got 2 glasses of water and a pail. You are instructed to pour both glasses of water into the pail. Question is, how will you be able to know which part of the water in the pail belong to which glass? This is a question poised to me by a 14 years old school kid...it kept me thinking for hours....
I came across this interesting facts about liquid and solid while revising for the coming Monday test, almost all materials are more dense in solid state than in liquid state. That means when molten aluminium, copper or steel solidifies in a casting, it actually shrinks! Which means if you were to pour 1 litres of molten steel into a cylindrical casting, after solidification, it might end up occupying 0.9 litres. The same old law applied, "mass cannot be created or destroyed" thus in this case 1 litre (volume) of molten steel will have the same mass as 0.9 litres of solid steel and the only difference will be the density. If we were able to drop this solid steel into molten steel, it will be observed that the solid steel will sink.
However water undergoes an interesting process, instead of shrinking when it freezes (solidify), it actually expands! And due to this expansion or increase in volume, ice (solid water) had less density than water (liquid), thus ice floats. Ta da!!!! For those interested in the figures, water volume expands 8.3% when it freezes. That explains why your coca-cola and pepsi cans become bloated when you freeze it in the chiller. That also explains why soft drink maker will never fill up the entire can or else the absents minded who wanted a quick chill of their soft drink might end up with a big freezer mess from exploding cans (over expansion).
Now here is a little IQ question involving water. You got 2 glasses of water and a pail. You are instructed to pour both glasses of water into the pail. Question is, how will you be able to know which part of the water in the pail belong to which glass? This is a question poised to me by a 14 years old school kid...it kept me thinking for hours....
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