You must’ve often wondered why Newspapers turn yellow when they become old.
Paper is made from wood,which is made up mainly of white cellulose and a dark substance called lignin. The lignin molecules, when exposed to oxygen in the air, become oxidized, giving off a darker color
Fish do not have vocal chords. They rattle their bones, gnash their teeth., and vibrate muscles against their swim bladder ,producing a variety of low-pitched sounds to convey messages to each other.
Hot water contains the energy used to raise its temperature while steam contains not only the energy needed to raise its temperature but also the energy used to convert it from the liquid state to the vapour state.
So steam holds much more energy than hot water.
When steam touches your hand, it condenses back to water and cools; releasing much more heat than hot water does.That’s why a steam burn is much more painful than a hot water burn.
Why is a steam burn more damaging than a burn with boiling water of the same temperature?
Ever wondered what makes curry stains in your clothes turn red when they come in contact with detergent?
Curry stains usually contain Turmeric which has a pigment that lends the yellow colour to it as well as another pigment
that is reddish orange in colour. When turmeric comes in contact with detergent, it reacts with the fatty acids
present in the detergent hence the reddish orange pigment gets more active than the yellow one making the turmeric appear red.
Did you know that many Baby birds have an “egg tooth” that help them break out of the shell?
The beak and the claws of the bird are not fully developed and cannot penetrate the egg shell yet.so this tiny knob at the tip of the beak helps the bird break through the shell and is lost soon after the egg is hatched.
Have you ever had a drink of cool refreshing water from a clay pot? Do you know what makes the water stay so cool?
A clay pot has many small pores .Water seeps out through them and evaporates from the surface of the pot.The energy needed for evaporation is taken from the water kept in the pot. As a result, water kept in the pot becomes cool.
The filament of a bulb is made out of tungsten that is heated to produce white light.
When the bulb is being used, minute quantities of the tungsten undergo sublimation-a process of conversion from the solid state to the vapour state. The tungsten vapours become deposited on the inner surface of the bulb, and the deposit builds up gradually to produce a dark spot.
Have you ever examined a burned-out filament bulb and wondered why there is a dark spot on the glass?
Have you ever wondered why tarnished brass or copper items like coins and vases are cleaned with vinegar or lemon?
Their surfaces are tarnished on prolonged exposure to air, forming compounds that range in color from black to blue to dark green.These compounds dissolve in acidic solutions like the acetic acid in vinegar & the citric acid in lemon juice,making them shine like new.
Do you know how stitches on wounds stay in a place long enough to promote healing and then disappear? These stitches are made from natural materials, such as processed collagen, silk and hair, as well as some synthetic polymers that degrade by reacting with water or with enzymes in the body. The degradation products are carbon dioxide and water, which are produced in minute quantities that they do not affect the body.
Have you heard of buildings that have no air conditioning yet stay cool? The ‘East Gate’ situated in Zimbabwe cools itself using fans on the first floor that suck in outside air and then push it up along a central spine.But do you know that this technology was inspired by termite hills? These hills are built in a specific way so that air is sucked from the lower part and travels up as convection currents through ducts maintaining its temperature
The reason for why some eggs crack when boiled is linked to
the presence of an air pocket at one end of each egg, just beneath the shell. When an egg is heated, its air pocket expands.
If the water is boiled too fast, the expanded air does not have time to diffuse through the porous shell, causing the shell to crack.
You may have tried to hard-boil eggs and found that some eggshells crack in the process. Why does that happen?
It is estimated that a plastic container can resist decomposition for as long as 50,000 years.
The human eye is so sensitive that if the Earth were flat, in complete darkness you could spot a candle flickering,from up to 30 miles away.
Have you ever wondered how sharks swim so speedily? The surface of shark skin is covered in tiny teeth like structures. The shape and positioning of these structures vary across the sharks’s body , managing the flow of water in the most efficient way and reducing resistance. This technology has been used to create an efficient bodysuit that is used by swimmers at the Olympics.
Crocodiles are cold blooded animals and do not have sweat glands. So They often sleep with their mouths open and release heat through their mouths.
Have you ever wondered why crocodiles sleep with their mouths open?
You may have often wondered how some Birds easily chew chilies? As you know, the capsaicin in chilies is what gives the burning sensation.But some birds like parrots do not have the capsaicin-sensitive receptor on their tongues; which is why they enjoy chilies so much.
Can you believe that we are about 1 cm taller in the morning than in the evening? The cartilage between our bones gets compressed by standing, sitting and other daily activities as the day goes on, making us just a little shorter at the end of the day than at the beginning.
Have you noticed the difference between normal paper and money?Normal paper — including notebook paper, newspaper is all made out of cellulose, which comes from trees. Paper money, on the other hand, is made from 75% cotton and 25% linen fibers which is why money is not that much affected by water.while normal paper comes unglued when it’s soaked in water.