HOT WATER FREEZES FASTER THAN COLD WATER

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.




;)

WHAT ARE FULLERENES...????????????

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.





;)

WHAT IS A DIELECTRIC.....?????

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.




;)

HOW TO MAKE WATER FREEZE INTO ICE INSTANTANEOUSLY ..?????????

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.

REVERSE OSMOSIS or "RO"

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...THE MOST INTERESTING SOLID...WHAT S THAT ???

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.

;)

WHY ALUMINIUM DID NOT CORRODE FASTER THAN IRON , ALTHOUGH IT IS MORE REACTIVE......??????

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.

;)

WHAT IS POLYMERIZATION...??????????????

Polymerization is defined as any process in which relatively small molecules called monomers , combine chemically to produce a very large chainlike or three-dimensional network molecule called polymer.

The monomer molecules may be all alike or they may represent two , three or more different compounds.

POLYTHENE is a best suited example for this process.

In this case ethene is a monomer and the three-dimensional network of ethene creates a Polythene , which is a polymer and the whole process is called polymerization.

RADIOACTIVITY and ITS EFFECTS.....??????

Radioactivity is the process by which unstable atomic nuclei release energetic particles to become stable.

The energy and particles released during the decomposition process are called radiation.

When unstable nuclei decomposes in nature the process is referred to as natural radioactivity. 

When the unstable nuclei is prepared in the laboratory , the decomposition is called induced radioactivity.

HEALTH EFFECTS DUE TO RADIOACTIVITY :----

Radioactive materials that decay spontaneously produce ionizing radiation.

Any living tissue in the human body can be damaged by ionizing radiation in a unique manner.

Sometimes body can repair that damage by itself but sometimes the damage is of a nature that can not be repaired.

Some other effects are Hair loss , changes in blood chemistry , vomiting , fatigue e.t.c.

HOW DOES NITROUS OXIDE HELP AN ENGINE TO PERFORM BETTER...??????

When you heat nitrous oxide ( N2O ) or NOx to about 300 degree celcius , it splits into nitrogen and oxygen.

So the injection of nitrous oxide into an engine means that more oxygen is available during combustion.

Because you have more oxygen you can inject more fuel , allowing the same engine to produce more power.

Nitrous oxide is one of the simplest way to provide a significant horsepower boost to any gasoline engine.

NOx has another effect that improves performance even more.

When it vaporizes , nitrous oxide provides a significant cooling effect on the intake air.

When you reduce the intake air temperature , you increase the air's density and this provides even more oxygen inside the cylinder.

;)

WHAT IS A FERRITE....????

A Ferrite is a type of ceramic compound composed of iron oxide ( Fe2O3 ) combined chemically with one or more additional metallic elements.

They are ferrimagnetic , meaning that they can be magnetized or attracted to a magnet , and are electrically noncondutive.

Ferrites can be divided into two families based on their magnetic coercivity , it is their resistance to being demagnetized.

Hard ferrites have high coercivity , they are difficult to demagnetize.

They are used to make magnets for devices such as refrigerator magnets , loud speakers and small electric motors.

Soft ferrites have low coercivity.

They are used in the electronics industry to make ferrite cores for inductors and transformers and in various microwave components. 

;)

WHAT ARE CERAMICS AND THEIR CATEGORIES.....???????????

Ceramics can be defined as heat-resistant , non-metallic , inorganic solids that are generally made up of compounds formed from metallic and non-metallic elements.

Although different types of ceramics can have different properties , in general ceramics are corrosion-resistant and hard , but brittle.

Most ceramics are also good insulators and can withstand high temperatures.

These properties have led to their use in virtually every aspect of life.

The two main categories of ceramics are :---   Traditional and Advanced

Traditional ceramics include objects made of clay and cements that have been hardened by heating at high temperatures.

These are used in dishes , crockery , flowerpots..e.t.c.

Advanced ceramics include carbides such as silicon carbide ( SiC ) e.t.c.

These act as good superconductors that is why they are used in making sockets..e.t.c.

:)

WHAT IS CETANE NUMBER.....??????????????

Cetane number or CN is an indicator of the combustion speed and combustion quality of diesel fuel.

The higher the cetane number the more easily the fuel will combust in a compression setting ( such as a diesel engine ).

The characteristic diesel " knock " occurs when fuel that has been injected into the cylinder ignites after a delay causing a late shock wave.

Minimizing this delay results in less unburned fuel in the cylinder and less intense knock.

Therefore  higher - cetane fuel usually causes an engine to run smoothly and quietly.

This does not necessarily translate into greater efficiency , although it may in certain engines.

;)

WHY DIESEL CANNOT BE USED IN PETROL ENGINE...?????????

It is just because Petrol is more volatile then Diesel.

Also we know that petrol is ignited by spark and diesel by compression ignition in engine.

That's why if we use diesel in petrol engine , the carburetor cannot produce fine vaporized mixture of air-diesel due to low volatility of diesel.

Now when this improper air-diesel mixture reaches the combustion chamber.

Then the spark produced in chamber will only burn diesel properly and rest of the mixture will not get enough heat from the fire produced by the spark.

Hence unburnt mixture will tend to various efficiency loss , this is due to the improper penetration of fire.

The improper penetration of fire results from improper vaporization of air-diesel mixture and it results from low volatility of diesel.

This is the reason why Diesel cannot be used in Petrol engine..

;)

WHAT IS CORROSION , DRY and WET CORROSION....???????

# CORROSION  :---        The loss of materials (                                            metals and alloys ) or its useful properties by chemical and electrochemical interactions with its environment is called     corrosion.



# DRY CORROSION  :---       Dry Corrosion                                                         occurs when there is no water and moisture to aid the corrosion , and the metal oxidises with the atmosphere alone.


# WET CORROSION  :----       Wet Corrosion of                                                   metals occurs through electron transfer , involving two processes oxidation and reduction.
  
 In oxidation metal atoms loose electrons , the surrounding environment then gains the electrons in reduction. 

;)

WHAT IS A CARBON NANOTUBE..?????

Currently , Scientists find two nano-size structures of particular interest nanowires and carbon nanotubes. In the last couple of years carbon nanotubes have overshadowed nanowires.

A Carbon nanotube is a nano-size cylinder of carbon atoms.Imagine a sheet of carbon atoms , which would look like a sheet of hexagons.If you roll that sheet into a tube , you'd have a carbon nanotube.

Carbon nanotube properties depend on how you roll the sheet.In other words even though all the carbon nanotubes are made of carbon , they can be very different from one another based on how you align the individual atoms.

With the right arrangement of atoms , you can create a carbon nanotube that's hundreds of  times stronger than steel butsix times lighter.

Engineers plan to make building materials out of carbon nanotubes , particularly for things like cars and airplanes.

Lighter vehicles would mean better fuel efficiency , and the added strength translates to increased passenger safety.

;)

OPTICAL PUMPING

Optical pumping is a process in which light is used to pump electrons from a lower energy level in an atom or molecule to a higher one.

It is commonly used in laser construction to pump the active laser medium so as to achieve population inversion ( i.e :-- no. of electrons in the excited state is more than that of in the ground state ).

;)

MY FIRST BLOG....

This is my first blog....Jai Shree Ganesha...

:)