Yeah its true that hot water freezes faster than cold water.
This is basically due to the Mpemba effect.
According to the Scientists of Nan Yang University in Singapore , its answer lies in the bonding between the water molecules.
As we know that every water molecule has 2 Hydrogen atoms bonded to a 1 Oxygen atom by means of covalent bonds , which means they can share electrons with each other.
So According to the Scientists , when water molecules are close together their natural repulsion causes the covalent bonds to stretch and store energy.
As the water warms up it becomes less dense , the Hydrogen bonds stretches the molecules to move further apart.
When the Hydrogen bonds stretch they allow the covalent bonds to shrink and release their energy and this is equivalent to cooling.
So according to the Nan Yang theory hot water essentially able to release energy faster then cold water and leading to a quicker freeze.
;)
A Fullerene is a pure carbon molecule composed of at least 60 atoms of carbon.
In Fullerene molecules of carbon are present in the form of a hollow sphere , ellipsoid , tube and many other shapes.
Spherical fullerenes are also called Buckyballs and they resemble the balls used in football ( soccer ).
Cylindrical fullerenes are called carbon nanotubes or buckytubes.
Buckyminster fullerene is one type of fullerene.
Its molecules have 60 carbon atoms arranged in a hollow sphere.
;)
Dielectrics are insulating materials or a very poor conductors of electric current.
Now you can see here in the diagram that , when the dielectrics are placed in an electric field , practically no current or very less current flows in them because , unlike metals , they have no loosely bound or free electrons that may drift through the material.
Instead electric polarization occurs also known as dielectric polarization.
Because of dielectric polarization the positive charges within the dielectric are displaced minutely in the direction of the electric field , and the negative charges are displaced minutely in the direction opposite to the electric field.
This separation of charge or polarization reduces the electric field within the dielectric.
;)
Have you ever seen water freeze instantaneously ?
Well guys , I am going to tell you how it happens..???
To get this " instant ice " effect , put some unopened bottles of water in the freezer for anywhere between 90 to 115 minutes.
The water gets supercooled ( below freezing ) , but does not actually freeze because the water does not contain enough impurities.
When you put that supercooled water on an ice crystal , it turns instantly to ice.
It will also do this if the bottle is hit hard enough.
I think we all should heard about Aquaguard RO water purifier.
It is Aquaguard Reverse Osmosis.
Reverse Osmosis or " RO " is a water purification technology that uses a semipermeable membrane to remove larger particles ( i.e :- salts ) from drinking water.
In Reverse Osmosis , an applied pressure is used to overcome osmotic pressure.
Reverse Osmosis can remove many types of molecules and ions from solutions , including bacteria and is used in both industrial processes and the production of potable water.
:)
Aerogel , also known as Frozen smoke , is the world's lowest density solid , composed of 96% air.
If you hold a small piece of Aerogel in your hand , its practically impossible to either see or feel.
But if you poke it , its like styrofoam.
It supports upto 4,000 times its own weight and can withstand a direct blast from two pounds of dynamite.
It is also the best insulator in existence.
Aerogel was used by NASA to help insulate the electronics on the Mars Exploration Rovers.
;)
We know Aluminium is more reactive than Iron.
So it reacts faster with the oxygen in the air forming Aluminium oxide,
Aluminium oxide is very unreactive , because once the oxide layer forms on the aluminium surface , it binds very tightly to the surface of the Aluminium , so no cracks can form that cause further corrosion.
This idea is used to prevent the Iron from corrosion by covering it with a thin layer of less reactive metal.
This process of covering of metal is known as Galvanizing.
;)
