Ice
See some
Experiments on Ice
Is Ice a Mineral?
Yes, Ice is a mineral and has been
formally described in Dana's "System of Mineralogy".
[www.livescience.com]
Riddle of Water and Ice
You have water, and you have ice. You freeze the water, and after it is
frozen, you get the ice. Have you ever thought why :
1. A Coca-Cola can bursts out when frozen? OR
2. The ice trays are left a little bit empty before they are kept in freezer? OR
3. A closed bottle is not filled up to the brim with water when it needs
to be frozen? OR
4. When the ice is melted in a cup, its water doesn't overflow? (see below for
their answers)
Because water
expands when frozen. How do you know how much this water expands when
frozen? The volume of the ice is 10% more than the water kept for freezing.
So the ice is only 10% more, that is why 10% space should be left empty
when any liquid is frozen. And that is why when ice is melted, its water
takes less space than ice - how much? only 10% less.
Another Fact About Water and Ice - Iceberg
You must have read and heard about
icebergs in your geography class and you must have seen some picture or photograph
of the iceberg too. Have you heard the saying, "You are seeing only the tip
of the iceberg.". This saying is 100% true, because when you see any iceberg
you see only its tip - "tip" means "very little", and you are
really seeing very little of the iceberg. because its most part is inside the water.
Now can you guess how much you are seeing above the water? 50%? 40%? 20%? Only 10%.
90% of the iceberg is inside the water. One should be very careful about the iceberg,
because you can never guess about the iceberg.
Which Shape of Ice is Melted First?
You are a shape lover. You have frozen your colored sweet water in different
shapes - round like a ball, squares, thin rectangles, cylinders etc. All
shapes have equal amount of water. Now you have distributed those shapes to
your friends - one shape to one friend and another shape to another friend.
Whose ice will melt first? Whoever's shape is the widest and longest in area.
Thus the ball like shape will take longer time to melt than the thin rectangle
one.
Its corollary is,
that if you want to keep water in frozen shape for longer time, freeze it in
balls. They will stay as ice for longer time.
Why Doesn't the Water Come Out of the Cup When Ice Cubes are Melted in it?
As you have known above that ice has larger volume than water, how much it
is? It is 1/10th of the water. And only 1/10th part of a floating iceberg
can be seen above water. When the ice is frozen, its volume is increased
1/10th time. In the same way when the ice melts, its volume is decreased
1/10th time. Therefore the water from melted ice will take only that
much space, whatever it took when it was floating as ice. Thus the water
from melted ice cubes cannot overflow the cup,
UNLESS THE CUP IS ALSO OVERFILLED WITH ICE CUBES.
Can You Make Ice Without Refrigerator?
Now a days most people have refrigerator in their homes. So you keep water
in refrigerator and after some time the ice is ready to be used. But think
of a little over a century before. How people froze their water? Or from
where they made their ice cream?
Before mechanical
refrigeration system was introduced, people used to cool their foods with
ice and snow either found locally or brought from mountains. The first
coolers were the holes dug in the ground, lined with wood or straw packed
with ice and snow. The first well known artificial refrigeration was
demonstrated in Glasgow in 1748, but it could not be put in use until an
American introduced a refrigeration machine in 1805. But it was not until
about 1929 that the modern refrigeration came into existence.
Yes, you can make
ice without your refrigerator. But how? It is a very old trick. Now what we
are going to tell you, it was known perhaps, at some point, to Chinese in
14th century or to Italians in 17th century that a container placed in salted
water would stay cool for longer time than usual. On the same principle, if
you put a small jar of sweet milk in a large bucket or pan and fill the empty
space around it with ice and sprinkle a lot of salt on the ice. After 20-30
minutes you will find that your sweet milk has started freezing. So it is the
salt that helps the things freeze, and keep them cool for longer time. Only
after mixing salt or something else in the ice, the temperature of ice will
not go higher than 32 degree Fahrenheit. This temperature point is required
to freeze water.
Why Can't You Skate on Glass?
Glass is more slippery than ice, then why can't you skate on glass? Because
when you skate on ice, their blades melt the ice under them, and you can
slip on water easily. Thus when you are skating on ice, you are not skating
on ice, but on water. But mind it, you cannot skate in river. Why? Because
even if you are skating on water, when you are skating on ice, still there
is hard surface below your skates, but in river that hard surface is not be
there to put your foot on.
How Much Would Sea Rise If The Whole Antarctica Ice Sheet Melted?
Can You Guess? Antarctica Ice Sheet holds nearly 90% of the world's ice and
70% of freshwater. If the entire ice melted, it would rise the sea level by
220 feet (almost 10-story building high. Scientists say that by 2100 the sea
would rise above 3 feet.
[Yahoo, 5/17/2008]
First Ice in India
The first ice arrived in India,
in Kalkattaa, Bangaal in 1833 from New England, USA. Then Frederic Tudor of
Boston discovered that it would remain frozen if covered in sawdust. So Tudor
started cutting ice blocks in New England winter and transporting them all
around the world. The "Ice House" in Madraas was built in early
1840s and survived for about 30 years until refrigeration was invented. Later
it was named "Vivekaanand House".
[India Handbook, p 868-888]