Shiva Thapa (56kg) was the lone Indian boxer to make the final after Olympic-bound Vikas Krishan (69kg) settled for a bronze medal following his loss in the semifinal of the 43rd men’s and women’s Grand Prix in Usti nad Labem, Czech Republic.

Shiva, who has been picked in the team for next month’s Asian Olympic Qualifiers in Kazakhstan, defeated Czech Republic’s Patrik Velky 9-5. He will now face Vittorio Jahyn Parrinnelo of Italy in the summit clash.

Vikas, on the other hand, lost to Cuba’s Despaigne Arisnoide 9-14.

“Both the boxers fought well but unfortunately Vikas lost. Shiva has been in good form ever since he came on the senior level last year and he showed why he is considered a promising talent. He was sharp as usual with his reflexes and has a solid defence,” coach Jagdeep Hooda, who is with the team, told PTI from Usti nad Labem.

1.Global warming is due to increased production of

Answer : Carbon dioxide

2. Which acid is present in lemon

Answer : Citric acid

3.Brass is an alloy of copper and

Answer : Zinc

4. The hardest natural substance known in the world is

AnswerAnswer Answer : Diamond

5.Permanent hardness of water may be removed by the addition of

Answer : Sodium carbonate

6.Which is the most commonly used bleaching agent

Answer  : Chlorine

7. Which of the following gas is used in cigarette lighters

Answer : Butane

8. Baking Soda is also known as

Answer : Sodium bicarbonate

9. Bond order of a molecule can be at the maximum of

Answer : 3

10. Neutral molecules in which one of the carbon atoms has six valence electrons are called

Answer : Carbenes

11. Which of the following is non-radioactive

Answer : Deuterium

12. Which of the following is a thermo setting plastic

Answer : Bakelite

13. Octane number of petroleum can be increased by

Answer :Atomizationa

14. Atoms of the same element having the same atomic numbers but different atomic weights are called

Answer : Isotopes

15. What is the main constituent of soap

Answer : Sodium hydroxide

16.Name a fertilizer that contain maximum amount of Nitrogen

Answer : Urea

17.Which compound is called oil of wintergreen

Answer : Methyl Salicylate

18. What is alum

Answer : Potassium Aluminium Silicate

19. A minute amount of radio isotope is called

Answer : Tracer

20. Name an alloy of copper, antimony and tin

Answer : Babbitt metal

Endosulfan is an organochlorine compound that is used as an insecticide and acaricide. This colourless solid has emerged as a highly controversial agrichemical due to its acute toxicity, potential for bioaccumulation, and role as an endocrine disruptor. Banned in more than 63 countries, including the European Union, Australia and New Zealand, and other Asian and West African nations, and soon in the United States, it is still used extensively in many other countries including India and Brazil.

Because of its threats to the environment, a global ban on the use and manufacture of endosulfan is being considered under the Stockholm Convention.

Health effects

Endosulfan is one of the most toxic pesticides on the market today, responsible for many fatal pesticide poisoning incidents around the world.

Endosulfan is also a xenoestrogen—a synthetic substance that imitates or enhances the effect of estrogens—and it can act as an endocrine disruptor, causing reproductive and developmental damage in both animals and humans. Whether endosulfan can cause cancer is debated.

Take a Pledge : Ban Endosulfan and Save lives and Environment!

Sodium Silicate (Na2o, Sio2)

Sodium Silicate is a compound mixture of sodium oxide i.e. Na2o with silica sand i.e. Sio2 with water. Sodium silicate is also called water glass. There are two process to manufacture liquid Sodium Silicate.

To manufacture a lower ratio of Sodium Silicate by Hydrothermal process.

Mixture at Na2Co3 (Soda Ash) with Sio2 (Silica sand) in furnace fuses  of more then 1100oC gives sodium silicate glass in lumps form which is  easily dissolved in hot water.We manufacture large range of sodium silicates, as per the customer’s specific requirements.

Three scientists won the Nobel Prize in chemistry today for developing a process that, among other things, helps synthesize medicines.

Richard Heck, Ei-ichi Negishi and Akira Suzuki were cited for their work in “palladium-catalyzed cross couplings in organic synthesis.” That’s a way of joining together carbon atoms — using the element palladium as a catalyst — in a more efficient and precise way than was previously done. And joining together carbon atoms helps scientists do a lot of nifty things, including making medicines.

Covalent bonds are chemical bonds between two non-metals, for example between H and O in water (H₂O). As they are both non-metals—which need to gain electrons—they have to share, so their outer shells cross over in order to have a full outer shell. A full outer shell has eight electrons.

With water the oxygen atom shares one electron with each hydrogen atom and the hydrogens also share one: this means that the hydrogen atoms have two each and the oxygen atom has 8.

Covalent bonds are mostly weaker than ionic bonds, and have a lower melting point in comparison. They are also thought to be poor conductors of electricity. Most scientist cannot figure out why these bonds happen. They say that John Mendel discovered them in 1867.

Ionic bond

An ionic bond is the bonding between a non-metal and a metal that occurs when charged atoms (ions) attract after one loses one or more of its electrons, for example berries and chloride. This makes the bond stronger and harder to break.

in other words, it is the attraction between 2 oppositely charged ions. The positive ion is called cation, and the negative ion is the anion.

Chemical bonds are what join together atoms. When two or more atoms are in a chemical bond they stay joined unless the needed amount of energy or more is transferred to the bond. Something different can then happen. Chemical bonds can be explained using different theories. Some of these theories try to explain chemical bonds in a simple way that can be used by chemists to imagine what could happen when they try to make molecules. Some explain how the atoms are bonded together with more detail and are used by chemists and physicists.

A plastic is a material that can change its shape, so many things can be made of plastic. There are many types of plastic. Some can be shaped only when they are freshly made; then they become hard afterwards. Others can be changed by heating them up or even by melting them.

Most plastics are man-made; they do not occur in nature. They are often made from oil that comes out of the ground. The process of making plastics is usually quite complicated. Most of the materials that are called plastic are polymers. Polymers are long chains of atoms bonded to one another.

People experimented with plastics based on natural polymers for a very long time. Alexander Parkes, an English inventor (1813-1890), created the earliest form of plastic in 1855. It was hard but flexible and transparent, and he called it “Parkensine.”

Dalton’s Law of Partial Pressure

It states that the total pressure exerted by a mixture of different gases in a given space is equal of sum to partial pressure of each constituent gas where partial pressure of a gas is the pressure exerted by it, if it were to occupy the same space alone.

Law of Indestructibility

It states that matter can neither be created nor destroyed by any chemical change.

Law of Multiple Proportion

It states that when two elements combine to form more than one compound, the mass of one which combines with the fixed mass of the other bears a simple ratio to each other.

Law of Reciprocal Proportion (or Law of Equivalent Proportions)

It states that when two different elements combine with the same weight of third element the ratio in which they do so will be the same or some multiple of the ratio in which they combine with each other, e.g., The elements C and H combine with the third element O to form CO₂ and H₂0. Also they combine directly to form CH₄ :

i.e., from this the ratio C : H = 3 : 1, Now in,

Law of Constant Composition

It states that a chemical compound always consists of same elements combined together in the same proportion by mass.

Gay Lussac’s Law of Combining Volumes

It states that gases react together in volumes which bear simple and whole number ratios to one another as well as to the volumes to the gaseous products whereas the volumes being measured under same conditions of temperature and pressure.

Law of Mass Actidon

It states that the rate of chemical reaction is proportional to the molecular concentration of each of reacting constituents.

Faraday’s Law of Electrolysis

1. The products of electrolysis appear only at the electrodes, having weight proportional to the quantity of electricity passed.
2. The amounts of ions liberated at the various electrodes are proportional to their chemical equivalents when current passes through the different electrolytes.

Ohm’s Law

It states that the magnitude of current flowing between two ends of a conductor is proportional to the potential difference between them.

Avogadro’s Law

It states that under similar conditions of temperature and pressure equal volume of all gases contain equal number of molecules.

Raoult’s Law

It states that the vapour pressure of a solution containing non – volatile solution is directly proportional to the mole fraction of the solvent.

The solutions which obey Raoult’s law are called Ideal Solutions

1. When solvent – solvent and solute – solute interactions are stronger than solvent – solute interaction positive deviations take place.

   PA > P°A . XA, PB < P°B . XB, ΔHmix = +ive, ΔV = +ive

2. When solvent – solvent and solute – solute interactions are weaker than solvent – solute interaction negative deviation takes place.

   PA < P°A . XA, PB < P°B . XB, ΔHmax = -ive, ΔV = -ive