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arihant obj is a single part.it covers all the concepts in a lesson
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1.An element's name must be approved by the International Union of Pure and Applied Chemistry, or I.U.P.A.C., in Geneva, Switzerland.
2.The heaviest element gas is radon at room temperature. (There may be heavier ones, but they are compunds not atoms). It was discovered by Friedrich Ernst Dorn in Germany in 1900, but he first called it niton, until 1923.
3.The lightest gas is hydrogen, it is also the lightest of all elements.
4.The element with the highest melting/freezing point is carbon at 6,381 degrees Fahrenheit (3,527 degrees Celsius).
5.The element with the highest boiling point is rhenium at 10,105 degrees Fahrenheit (5,596 degrees Celsius).
6.The element with the lowest melting/freezing point is helium at -458 degrees Fahrenheit (-272.2 degrees Celsius).
7.The element with the lowest boiling point is also helium at -452.07 degrees Fahrenheit (-268.93 degrees Celsius.
8.The word "atom" comes from the Greek word atomos, meaning "uncut."
9.In 1964, scientists in Russia discovered element 104, and suggested the name Kurchatovium and symbol Ku in honor of Igor Vasilevich Kurchatov. Then in 1969, scientists in the U.S. also found element 104, and propsed the name Rutherfordium (symbol Rf), in the honor of the New Zealand physicist Ernest R. Rutherford. To get the names past the I.U.P.A.C., it won with rutherfordium.
10.The first and relatively pure atom of tantalum was produced by von Bolton in 1907.
11.Andres Manual del Rio discovered what we call today vanadium. He called it panchromium, and then changed it to erythronium (red), after noting that upon heating it turned red. In 1831, Nils Gabriel Sefström (a Swedish chemist) was working with some iron ores and this matter was lead to honor the Northern Germanic tribes' goddess Vanadis due to its inspiration in multi-colors. In the same year, Friedrich Wöhler came into posession of del Rio's erythronium, and confirmed it to be vanadium, after Vanadis. The name Vanadium is now being used instead of del Rio's erythronium.
12.Hafnium was named after the city of Copenhagen, Denmark.
13.The heaviest type of lepton is the tau.
14.At 0 degress Celsius and 1 atmospheric pressure, one mole of any gas occupies approximately 22.4 liters.
15.Atomic weight is the mass of an atom relative to the mass of an atom of carbon-12 which has an atomic wieght of exactly 12.00000 amu.
16.If the atom were the size of a pixel (or the size of a period), humans would be a thousand miles tall.
17.It would require about 100 million (100,000,000) atoms to form a straight line one centimeter long.
18.The weight (or mass) of a proton is 1,836.1526675 times heavier than the weight (or mass) of an electron.
19.The electron was first discovered before the proton and neutron, in 1897 from English physicist John Joseph Thomson.
20.The neutron was discovered after the proton in 1932 from British physicist James Chadwick, which proved an important discovery in the development of nuclear reactors.
21.Carbon dioxide was discovered by Scottish chemist Joseph Black.
22.When silver nitrate is exposed to light, it results in a blackening effect. (Discovered by Scheele, which became an important discovery for the development of photography).
23.After firing 5 billion billion zinc ions at a speed of 18,460 miles per second (30,000 kilometers per second) at lead, the German scientists at Darmstadt, Germany created a single atom of 112 protons (ununbium) that survived for one third (1/3) of a millisecond.
24.If an electric current is passed through a solution or molten salt (the electrolyte), ions will migrate to the electrodes: positive ions (cations) to the negative electrode (cathode) and negative ions (anions) to the positive electrodes (anions).
25.The positron was discovered in 1932 by the U.S. physicist Carl Anderson at California Institute of Technology, United States.
26.Fritz Haber developed chlorine gas for use by the Germans in World War I. (Unable to live with his, his wife commited suicide in 1915).
27.The flatulence of a single sheep could power a small truck for 25 miles (40 kilometers) a day. The digestive process produces methane gas, which can be burned as fuel.
28.Cesiums has a diameter of 0.0000002 inches (0.0000005 millimeter).
29.Hydrogen atoms with no neutrons make up 99.985% percent of all hydrogen atoms. The remaining 0.015% percent contain one neutron.
30.The very first shell of an atom (innermost) can hold only up to two electrons.
31.Alkanes are also known as paraffins.
32.Alkenes are also known as olefins.
33.The first chemistry professor who taught chemistry only, in a regular appointed position in an educational institution of recognized standing, was Benjamin Rush, one of the signers of the Declaration of Independence, who taught as early as 1769.
34.Benjamin Rush (the first chemistry professor) published the very first chemistry textbook, called Syllabus of a Course of Lectures on Chemistry, in 1770 at Philadelphia, Pennsylvania.
35.Mercury is the only metal that is liquid at room temperature.
36.Africa's largest producer of mercury is Algeria (Africa's only producer of mercury), produces about one-tenth of the world's mercury.
37.The first compound discovered of an inert gas was xenon hexafluoroplatinate, by English chemist Neil Bartlett, in 1962.
38.It was Mexican chemist Mario Molina and U.S. chemist F. Sherwood Rowland that warned that the chlorofluorocarbons (CFCs) used in refrigerators may be damaging the Earth's ozone layer, in 1974.
39.The only two elements named after women are curium (Marie Curie) and meitnerium (Lise Meitner).
40.The element with the most isotopes are xenon with 36 (9 stable isotopes and 27 radioactive isotopes), and cesium also with 36 (1 stable isotope and 35 radioactive isotopes).
41.The most element that exists in both the Solar System and the Universe is hydrogen, at over 90%.
42.The most powerful nerve gas is VX, more correctly known by its scientific name Ethyl S-2-diisopropylaminoethylmethyl phosphonothiolate, was developed at the Chemical Defence Experimental Establishment, Porton Down, Wiltshire, United Kingdom, in 1952, and is 300 times more powerful than the phosgene (COCl2) used in World War I. A lethal dosage is 10 milligrams. It's usually green and smells of rotting fish.
43.The smallest ice, was created by Roger Miller and Klaus Nauta in the University of North Carolina, U.S.A., in 1999. It is 6 water molecules arranged in a hexagon, theoretically the smallest ice possible.
44.The sweetest chemical compound is sucronic acid.
45.The mass or weight of the neutron is 1838.683655 times greater than the mass or weight of the electron.
46.The mass or weight of the proton is 0.99862347855 times greater than the mass or weight of the neutron.
47.The mass or weight of the neutron is 1.00137841887 times greater than the mass or weight of the proton.
48.The proton was discovered by Ernest Rutherford in 1919.
49.The mass or weight of an electron is 0.0005446170232 times that of the mass or weight of a proton.
50.The mass or weight of an electron is 0.0005438673462 times that of the mass or weight of a neutron.
51.Paper kindles or ignites at a heat termperature of 450 degrees Fahrenheit (230 degrees Celsius).
52.The only substance other than water that is less dense as a solid than as a liquid is bismuth.
53.The first organic compound to be synthesized from inorganic ingredients was done by Friedrich Wöhler in 1828 from synthesizing urea from ammonia and cyanic acid.
54.Helium was first identified when French astronomer Pierre-Jules-César Janssen obtained evidence for the existence when observing the solar eclipse of 1868 in India when he detected a new yellow line, at 587.49 nanometers, in the solar spectrum.
55.The first national chemical society in the United States was the American Chemical Society, organized in New York City on April 20, 1876. Their first president was John William Draper.
56.The first atom of darmstadtium (element 110) was detected on November 9, 1994, 4:39 p.m. at the Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany. The isotope discovered has an atomic number of 269 (that is, 269 times heavier than hydrogen). It was produced by fusing a nickel and a lead atom together.
57.The horizontal rows of the periodic table are called periods.
58.The vertical columns of the periodic table are called groups.
59.Each electron of an atom has four quantum numbers, which apply to its shell, subshell, orbital, and spin.
60.The hottest flame is carbon subnitride (C4N2), which at 1 atmospheric pressure it's flame is calculated to be 9,010 degrees Fahrenheit.
61.The most ductile element is gold, which at one ounce it can be drawn to a length of 43 miles.
62.The solid substance with the lowest density is aerogel.
63.Boron becomes liquid at 3,769 degrees Fahrenheit (2,076 degrees Celsius), and is so corrosive that it cannot be contained at all
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The Five Card Trick
This trick makes you look like you're a mind reader! In fact it's just the sort of thing to scare away AN EVIL GOLLARK from the planet ZOG. First you need to make up the five special cards like the ones here: 
You'll see they are numbered 1 - 5 in BLACK on one side and 6 - 10 in RED on the other side. Make sure that the "6" is on the reverse of the "1" and the "7" is on the reverse of the "2" and so on.
The cards can be any size you like, but if you're going to carry them round, make them credit-card size. You're now ready to play your trick! - Pass the five cards to a friend and then TURN YOUR BACK! You are going to do the whole trick without even looking!
- You ask your friend to drop the cards one by one on the floor.
- Ask your friend to tell you how many RED cards are facing upwards.
- Ask your friend to add up the total showing on all five cards.
- But before your friend has finished - you can shout out the answer!
- Remember - you haven't seen the cards at any point since you started the trick!
THE SECRET:
If your friend says there are NO red cards, the total will be 15. (Because if all the black numbers are showing the total must be 1+2+3+4+5 = 15.)
If there are any red cards showing, you ADD an extra 5 on for every red card.
So if your friend says there are 2 red cards, you add 2 x 5 = 10. This would make the total 10 + 15 = 25. It would not matter which two cards are red!
Of course if ALL the red cards were showing, the total would be 15 + 25 = 40. You can probably do this trick two or three times before they start to guess the secret!
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The product of a 4-digit number and 10,001 + 2001 is: - the four digits, repeated once
- add 2001.
Example: 6741 × 10001 + 2001 - 6741 × 10001 = 67416741
- 67416741 + 2001 = 67418742
Create variations by changing the number to be added or subtracted - just make the number an easy one to handle mentally.
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- Choose a number with repeating 3's and a final 8.
- The square is made up of:
- the same number of 1's as there are repeating 3's in the number;
- one 4
- one fewer 2 than there are repeating 3's;
- a final 44.
Example: - If the number to be squared is 33338:
- The square has:
four 1's (same as
repeating 3's) 1 1 1 1
one 4 4
three 2's (one fewer than
repeating 3's) 2 2 2
a final 44 4 4
- So the square of 33338 is 1,111,422,244.
See the pattern? - If the number to be squared is 3333338:
- The square has:
six 1's (same as
repeating 3's) 1 1 1 1 1 1
one 4 4
five 2's (one fewer than
repeating 3's) 2 2 2 2 2
a final 44 4 4
- So 3333338 × 3333338 = 11,111,142,222,244.
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- Choose a 2-digit number.
- Multiply the number by 9.
- Divide by 2.
- Move the decimal point one place to the left.
Example: - If the number selected is 36:
- Multiply by 9: 9 × 36 = 270 + 54 = 324
- Divide by 2: 324/2 = 162
- Move the decimal point one place to the left: 16.2
- So 45% of 36 = 16.2.
See the pattern? - If the number selected is 52:
- Multiply by 9: 9 × 52 = 450 + 18 = 468
- Divide by 2: 468/2 = 234
- Move the decimal point one place to the left: 23.4
- So 45% of 52 = 23.4.
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Adding a series of quadruples - Have a friend choose a single digit number. (No restrictions for experts.)
- Ask your friend to jot down a series of quadruples (where the next term is always four times the preceding one), and tell you only the last term.
- Ask your friend to add up all these terms.
- You will give the answer before he or she can finish: The sum of all the terms of this series will be four times the last term minus the first term, divided by 3.
Example: - If the number selected is 5:
- The series jotted down is: 5, 20, 80, 320, 1280.
- Four times the last term (1280) minus the first (5):
4000 + 800 + 320 - 5 = 5120 - 5 = 5115
Divide by 3: 5115/3 = 1705 - So the sum of the quadruples from 5 through 1280 is 1705.
See the pattern? Here's one for the experts: - The number selected is 32:
- The series jotted down is: 32, 128, 512, 2048.
- Four times the last term (2048) minus the first (32):
8000 + 160 + 32 - 32 = 8,160
Divide by 3: 8160/3 = 2720. - So the sum of the quadruples from 32 through 2048 is 2720.
Practice multiplying from left to right and dividing by 3. With practice you will be an expert quad adder.
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Squaring numbers in the 300s - Choose a number in the 300s (practice with numbers under 310, then progress to larger ones).
- The first digit of the square is 9: 9 _ _ _ _
- The next two digits will be 6 times the last 2 digits: _ X X _ _
- The last two places will be the square of the last digit: _ _ _ X X
Example: - If the number to be squared is 309:
- The first digit is 9: 9 _ _ _ _
- The next two digits are 6 times the last digit:
6 × 9 = 54: _ 5 4 _ _ - Square the last digit: 9 × 9 = 81: _ _ _ 8 1
- So 309 × 309 = 95481.
For larger numbers reverse the steps: - Square the last two digits (keep the carry): _ _ _ X X
- 6 times the last two digits + carry: _ X X _ _
- Square the first digit + carry: X _ _ _ _
See the pattern? - If the number to be squared is 325:
- Square last two digits (keep carry):
25x25 = 625 (keep 6): _ _ _ 2 5 - 6 times the last two digits + carry:
6x25 = 150; 150+6 = 156 (keep 1): _ 5 6 _ _ - Square the first digit + carry:
3x3 = 9; 9+1 = 10: 1 0 _ _ _ _ - So 325 × 325 = 105625.
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Hofmann elimination (also known as exhaustive methylation) is a process where an amine is reacted to create a tertiary amine and an alkene by treatment with excess methyl iodide followed by treatment with silver oxide, water, and heat [1]. 
After the first step, a quaternary ammonium iodide salt is created. After replacement of iodine by an hydroxyl anion, an elimination reaction takes place to the alkene. With unsymmetrical amines, the major alkene product is the least substituted and generally the least stable, an observation known as the Hofmann rule. This is in direct contrast to normal elimination reactions where the more substituted, stable product is dominant (Zaitsev's rule). The reaction is named after its discoverer: August Wilhelm von Hofmann [2]. An example is the synthesis of trans-cyclooctene [3]: 
In a related chemical test called Herzig-Meyer alkimide group determination a tertiary amine with at least one methyl group and lacking a beta-proton is allowed to react with hydrogen iodide to the quaternary ammonium salt which when heated degrades to iodomethane and the secondary amine [4].
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I. Hair curling liquid:
Water =70 ml
Spirit of wine =30 ml
Borax =2gm
Perfume =sufficient quantity
Dissolve the borax into water and then mix the solution with spirit of wine. Add perfume in the last.
II. Metal Polish:
Water =675 ml
Triethanolamine=2 gm
Oleic acid =4 gm
Naphtha =360 ml
Clay or chalk =32 gm
Strong ammonia=6 ml
Dissolve the trienthanoamine in water and then add white stirring in the chalk. In separate container mix naphtha and oleic acid to uniform solution and add the first mixture to it. Stir and when a smooth emulsion is formed, add ammonia and store in bottles.
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| FLAME COLOR | CHEMICAL | | Blue | Copper chloride | | Carmine | Lithium chloride | | Green | Copper sulfate | | Orange | Calcium chloride | | Purple | Potassium chloride | | Red | Strontium chloride | | Yellow | Sodium chloride (table salt) |
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A Candle That Sucks Water Place a candle upright in the middle of a saucer. Fill the saucer with water. Light the candle. Place a glass over the candle. When the flame goes out, the water in the saucer will get sucked into the glass. How Does It Work? When the candle is burning inside the glass, the heat makes the air expand, so some of the air escapes outside the glass. The candle goes out after it uses up all the oxygen, so the air inside the glass cools. As it cools, the pressure inside the glass drops. Some of the carbon dioxide formed by the flame dissolves in the water as well, decreasing the pressure even more. The water outside the glass on the saucer is forced into the glass by the higher aire pressure outside.
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A Candle That Sucks Water Place a candle upright in the middle of a saucer. Fill the saucer with water. Light the candle. Place a glass over the candle. When the flame goes out, the water in the saucer will get sucked into the glass. How Does It Work? When the candle is burning inside the glass, the heat makes the air expand, so some of the air escapes outside the glass. The candle goes out after it uses up all the oxygen, so the air inside the glass cools. As it cools, the pressure inside the glass drops. Some of the carbon dioxide formed by the flame dissolves in the water as well, decreasing the pressure even more. The water outside the glass on the saucer is forced into the glass by the higher aire pressure outside.
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A Can That Can “Walk” Place an empty aluminum can on its side on the floor. Blow up a balloon and tie a knot in the end. Rub a tissue back and forth on the balloon. When you put the balloon near the can, the can will start rolling toward the balloon. How Does It Work? When you rub the balloon with a tissue, the balloon gets a negative electric charge of several thousand volts. When you put the balloon near the can, electrostatic induction affects the molecules in the metal. The outside of the can gets a positive charge, so it is drawn toward the balloon and starts rolling in that direction.
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| Here's a kooky tricky to spice up those dreary family barbecues. Aunt Meryl will marvel at the awesome altitudes your cups achieve.  | 1. Grab two identical, empty plastic cups. |  | 2. Nest one inside the other. |  | 3. Blow between the rims of the cups. |  | 4. Phoomba! The top cup launches up, up and away. Whoopy do eh?
Blow gently and the cup rises slowly ... wow man. | | what's going on? We all know that moving air can push things around but this cup seems to be getting pulled. Strictly speaking, the cup isn't really being pulled by anything. It is pushed up by air that is at higher pressure inside the cup. Two perplexing properties of all fluids are responsible.
First, the air you blow flows around the cup rather than just bouncing off the way a stream of bullets would ricochet off an impenetrable cylinder. This tendency of flowing fluids to 'stick' to obstacles is called the Coanda Effect. It's named after Henry Coanda who is widely regarded as the godfather of modern jet planes.
Second is the confusing fact that fluids exert less pressure when they flow across the surface of an object. This is called Bernoulli's Principle and as far as counterintuitive phenomena go, it's a doozey. The trick is to remember that fluids such as air and water are made of incredibly tiny molecules, which never sit perfectly still. Even when there is no net flow in a fluid, the molecules constantly jostle around, bumping into each other and bouncing off in all directions. Now the individual collisions molecules and large bodies such as yours don't really pack much of a punch. But multiply the tiny force of one collision by a kazillion and they add up to exert considerable pressure. It's a bit like being shot from every direction by trillions of tiny molecular bullets. You don't usually this pressure because it is equal in every direction. But when fluids flow across the surface of an object, there are less collisions directly against it. The molecular bullets graze along the surface, putting less pressure on it.
Let's combine these effects and get back to those cups. The air you blow hugs the area between the rims. Because it's flowing along this surface, there is now less pressure between the rims than before. But inside the bottom cup, the relatively still air is at the same pressure as before which is higher than the reduced pressure near the rim. This higher pressure air forces the top cup up and out of the bottom cup. Yippee. |
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| A chess queen can move in any straight line horizontally, vertically or diagonally. Click any square on the board to see where the queen can go. |
| | Here's the problem: Can you put EIGHT queens on the board so that none of them can go and attack another one? This classic puzzle was invented by the brilliant SAM LOYD and he claimed he knew 12 different answers! He also said there was only one answer where no three queens were in an exact straight line at any angle and that's the perfect solution that we've given you. But can you find the other 11? |
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Challenge a friend to try this trick!
Show your friend this diagram. They must try and draw it without going over the same line twice and without taking the pencil off the paper .
They'll never do it until you show them the sneaky method!
The Secret:
Start doing the drawing like this:
( Obviously you make your line touch at the corners and in the centre. We've just put gaps here to show how to draw it. ) Once you've got this far then you're stuck... or are you? To draw the last bit, fold the edge of the paper over ! 
Now you can finish the drawing and you haven't taken the pencil off the paper!
When you open out the paper again, you'll get the diagram as it should be. This sneaky trick might seem obvious now you know what to do, but if you try it on someone they'll be worrying about it for hours!
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Challenge a friend to try this trick!
Show your friend this diagram. They must try and draw it without going over the same line twice and without taking the pencil off the paper .
They'll never do it until you show them the sneaky method!
The Secret:
Start doing the drawing like this:
( Obviously you make your line touch at the corners and in the centre. We've just put gaps here to show how to draw it. ) Once you've got this far then you're stuck... or are you? To draw the last bit, fold the edge of the paper over !
Now you can finish the drawing and you haven't taken the pencil off the paper!
When you open out the paper again, you'll get the diagram as it should be. This sneaky trick might seem obvious now you know what to do, but if you try it on someone they'll be worrying about it for hours!
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Vriti Edustore
